BIQUARTERLY MAGAZINE OF THE SOCIETY FOR GENERAL

BI
MAGAZINE
OFTHE
FOR
SOCIETY
GENERAL
MICROBIOLOGY
VOLUME
26MAY
1999
QUARTERLY
Physicsunderthe microscope
T a x o n o mfyo rt h e n e wm i l l e n n i u m
How molecules
crossmembranes
Let'shavea debate!
F
Articles
SGMHeadquarters
Marlborouqh
House
Basinqstolie
Road
Wood
Spenciers
R e a d i nRoG 71 A E
T e t .0 f l B 9 B B 1 8 0 0
F a x 0 11 8 9 8 8 5 6 5 6
e-mailmtoday@
socgenmicrobiol.org.uk
SGMWebSite
http:,/www.socgen
microbiol.org.uk
Editor
DrDaveMcL.Roberts
Editorial Board
DrUlrichDesselberqer
rrolessoruaveKowtanos
ManagingEditor
JanetHurst
Produetion Editor
lanAtherton
Assistant Editor and
BookReviewManager
JaniceMeekings
Gontributions
Thesearealwayswelcomeand
shouldb'eaddressed
to theEditor
(c/o SGM Headquarters).
GopyDates
Lastdatesfor receiptof copy
at Marlborouoh
Houseare:
AOVefttSemen$
(vKU)
Auoustissue7 June
NoVember
issue11 October
Advertisements
Allenouiries
shouldbesenttor
InaCocks,
NWHSalesLtd,
CedarHouse,
CedarLane,
Frimley,
SurreyGU 16 sHY
Tel. 0127668511 I
Fax 012766850 1i
SpecialMailings
Allenouiries
shouldbesentto:
(SGM
JaniceMeekings
Headquarters)
T e l .0 11 8 9 8 81 8 0 2
F a x0 l l 8 9 8 8 5 6 5 6
e-mailj.meekings@
socgenmicrobiol.org.uk
Subscriptions 1999
NON-MEMBERS
MicrobioIogyToday940.OO
(us$70.00)
MEN/BERS
Allmembers
receiveMicrobiology
Today.ln addiliontheymaytake
journals.
anyoftheSociety's
OrdinarvMember
(inc.
Membeiship
Subscription
MicrobioIogy Today)937.00
(us$65,00)
(US$110.00)
Microbiotogy960.00
JGyS60.00(us$1
10.00)
(US$80.00)
/JSBC50.00
Studentor RetiredMember
(inc.
Membership
Subscription
MicrobioIogy Today)920.0O
(us$30.00)
(US$60.00)
MicrobioIogyS,32.00
JGyS32.00(US$60.00)
Theviewsexoressed
bv
contributors
arenotnecessarilv
thoseoftheSocietv:
norcanthe
claimsof advertiseis
be
guaranreeo,
O 1999TheSociety
forGeneral
Microbiology
ISSN:1464-0570
Design: GraphicsInternational
50
It'sallaquestionof image
Dave Roberts &Gianfranco Novarino
51
Atomicforce microscopyA lastairSmith
54
Cryo-electronmicroscopy:taking backthe knight
Stephen Fuller
56
C rystallographyandthe atomic anatomyof viruses
DavidLStuart,Jonathan M. Grimes,Nick Burroughs &
Peter P.C.Mertens
59
Nuclearmagneticresonance(N M R):keepingpacewith
microbiologyStephen Matthews
62
Whata Ramanspectrumcantellthe microbials6nlnnicl
NozomiYtow
64
Bacterialclassification
andtaxonomv:a'orimer'forthe new
millennium
HowardGest
70
Meeting preview:Delivering the goodsB ruce Ward
74
Let's have a d ebatel Philip Mortimer
77
Regular Features
LieneralUODV
Augustissue10May
issue13 September
November
Physicsunderthe microscopeDave Roberts
lnternationalDevelopmentFundreports
Above: Partofthe
structure
ofthecoreof
bluetongue
virus.
This issue ol M icrobiology
Todaylocuseson biophysics
andthe applications
that are
relevantto microbiology.
lt
includesin-deotharticleson
Ramanspectroscopy,CryoE M ,i m a g i n gN, M R , X - r a y
crystallography
and atomic
TOrcemrcroscopy,
PhotocourtesyJ. Diprose,
J.Grimes,
D.Stuaftand
R.Esnouf
,
Molecularmethodsare
revolutionizing
microbial
classification,
but on p.70
HowardGestquestionsthe
validityofsomeofthe resultant
changesto taxonomy.
The SGM meetingat
Edinburghwas a great
success.The nextmeetingat
Leedsin Septemberpromises
to be of equalmerit.The range
of interestingsymposiaare
outlinedon p.84 anda preview
o f t h e M a i nS y m p o s i u m ' H o w
Do Molecules Cross Microbial
Membranes?aoDearson
p,74.Also relatingto Society
m e e t i n g sP, h i l i pM o r t i m e r
raisesthe subjectof debates
as a meansof scientific
c o m m u n i c a t i o(np , 7 7 ) ,
Severalimoorianteventsto
fosterthepublicunderstanding
of science,suchas SETweek,
take placein the spring,SG M
is an activeoarticioantand
our recentactivitiesare
described
on o,90.
Thesealciclesaooearin
a d d i t i o nt o a l l t h er e g u l a r
featuresand reportsof
Societyactivities.
SocietyNews
February
CouncilMeeting
Notices
Newsof Members
Staff News
Grants
John RedwoodMPvisitsMarlborough
House
PrizeLecturesandAwaros
Meetings
Hotoffthe Press
Gradline
G o i n gP u b l i c
Reviews
AddressBook
SGM Staff
Diary
Comment
no
IZ
80
80
80
BO
8l
82
83
84
86
RO
90
92
95
96
103
104
Other ltems
Review:SGM
Symposium
Volume
57
DieterHaas
66
Feedback
94
IT
i.'
I
It's all a question of image
DaveRoberts
&Gianfranco
Novarino
History
I
I
I
I
I
i
I
II
i
of the specimen which are
ability to visualize microbial structures and processesis a
out of focus will clutter up
central part of the communication and, in many cases,the
and technically degrade the
understanding of our discipline.
Your eyesare forming an image of the letters on this page
I
I
I
I
I
I
gteater depth of field of
letter into its black and white components and so discern
lower numerical apeftures
its shape. If you were to move the page away from you,
with the lossof resolution to
the letters would form smaller and smaller images on your
get the bestcombination.
retina until you were no longer able to resolve the black and
white parts and only seethe text as a grey blur. The angular
separation of any two points on the page which can be
object is ofno use unlessyou
is called the acuity. Its absolute limit is when the two points
can see it; that is, it has to
To seesmaller objects, we can use lensesto form images
which
appear to be larger and thus are resolvable.
Magnifying glassesare an example of this principle, well
known for centuries. If it has been known for so long it is
reasonableto ask whether today's microscopesare really
better than those from the turn ofthe century or are they just
easier to use? Is there any new physics in the modern
i
Lensdesign a nd aberrations
I
The theory of microscope lensesand how to get the best
l
from them was essentially worked out by Ernest Abbe
I
I
II
t
II
working in the University ofJena, Germany. The formation
of an image by a lens depends on the diffraction of light.
School-levelphysics tells us how lenseswork, but there are a
number of imperfections in the image formed which arean
inevitable consequenceof the processof diffraction. For
example,the diffraction of light dependson its wavelength,
AB
OVE:
Two
species
ofthepeniculine
crliate
(green)
FrontonialF,
vernalis
andI
A number of ways to enhance the level of contrast have leucaslfuon
thesediment
ofEsthwaite
Water
Theblack
been developed.
background
indicates
that
themicroscope
was
setupfor
dark-field
illumination.
Each
cell
is
Stains, Perhaps the most obvious way to increasecontrast about
200pmlong
is to apply a stain. Surely every microbiologist must have
done a Gram stain, the first stage of which, staining with
crystal violet, demonstratesa clear increasein the contrast of
the objects. Bactetta that were once translucent become
an opaque purple and stand out clearly against their
background. The inverse ofthis process,negative staining
with, for example, nigrosin has the samegeneral effect.
Completion of the Gram stain illustrates a second
principle of staining, which is the capacity ro use chemical
different place for each component colour, resulting in
be made.
EI\LAY
COURTESY
BTANO
INSTITUTF
OI
FRESHWAIFR
ECOLOGY
BELOW:
pertitrich
Thesessile
Vorticella
sinilis
p h o t o g r a puhneddeDr I CN o t teh e
i l l u s i oonfo b l i q ui lel u m i n a tci oanu s e d
b yt h eb r i g h t e n ionfg
t h el e f ts i d ea n d
t h ed a r k e n i n
og
ft h er i g h et d g eT h e
rouno
d b j e ci tn t h el o w epr o r t i oonf
t h ec e l li st h ec o n t r a c t vi laec u o l e .
B a r1 0 0p m
COURTESY
NICOTA
IV]ILLER
SGl!1
images having a coloured fringe around the edge, and
basic kinds of aberration which are corrected by careful
design of the component parts of the objective lens, all of
which waswell understood by the end of the l pth century.
t
contrast, typically being completely opaque, which helps
to separatethe different components of lens performance.
reactionsto discriminate morphologically similar objects.
This is one areain which considerableprogresscontinues to
generally reducing the sharpnessof the perceived image.
t
be different from its background. Many microscope
test ob jects ate high-
so that an image formed with white light has a slightly
This is called chromatic aberration. There are a total of six
II
Contrast
The capacity to resolve an
separatedby your eye is a measure of resolving power and
instrument?
I
image. In realapplicationsit
is necessary to tfade the
becauseyou are able to resolve the adjacent parts ofeach
fall on adjacent retinal cells.
i
the depth of field and parts
A picture is wortb a tbousanduords, as the saying goes. The
Resolution
Traditional microscopy was, and in purist circles still is,
judged by the simple measureof resolution. Resolution is a
question ofhow closetogether two objects can be placed and
be perceivedastwo objects. It is almost entirely governed by
the angle formed bythe light from the edgesof the objects as
it entersyour eye and, therefore, the wider the cone of light,
the better the resolution. The light-gathering potential of
Dark field. \7hen light interacts with a specimen it may
do so in severalways. It may be occluded by an opaque
specimen, resulting in a silhouette, absorbedat one or more
wavelengths, resulting in a coloured image, or the light
may be re-directed or scattered. Light scattering by small
particles is known asthe Tyndall effecrand is the mechanism
by which we seedust motes in a sunbeam. The objects being
seen by this method are often too small to be resolvable
directly. Dark-field microscopy works by arnnging for the
objective lens to collect scatteredlight so that the specimen
is seen as a bright object against a dark background. In
technical terms this improves the signal-to-noise ratio and
gives a particularly powerful technique for detecting lowabundanceobjects.
the microscope objective is measured by its numerical
apertureand the greater the numerical aperture, the higher
higher the numerical aperture, the shallower the depth of
Phase contrast. Many microbes are essentially hyaline but
that does not mean they have no effect on the light which
passesthrough them, which may be changed in phase or
field will be. Real specimensare almost always thicker than
polarity, although neither change is visible to the eye. In
the resolution. The downside of this relationship is that the
ffitrfiffiffi#ffi6#e#ffiyroDAyvol26/MAy99
r
t
r
practice polarized light
OW:
U P PR
ER
(a)ln
aurea.
Nassula
The
ciliate
most
mlcroscopes are
t inodn
b r i g h t f lK
e lrdj h il lel ru m i n a a
commonly found in a
( b )w i t hD I CT h e si m
sh
s o twh a t
e age
d i { f e r eanstp e c t smineralogical context and
t h et w os y s t e rssh o w
t l Ci sn oat l w a y s
o ft h ec e lal n dt h aD
are uncommon in biology,
ch
t h ea u t o m a
t i oc i coefi l l u m i noant
but Frits Zernike was
0
s y s t eBma r s , 1p0m
NICOLA
[,1
LtER
SG[,1
IOURIESY
awarded the 1953 Nobel
L O WR
EO
RW:
( a )A nu n l d e n t isf lpeedc i oe fst h e
genus
cilLate
0xytricha
stichotrich
p h o t o g r aupnhdeeD
drI CT h e
blue
o ui sra na r t l f aocft h e
b a c k g r ocuonl d
cni r rci l e a r l y
DIC
c o n f i g u r aTt ihoe
v i s i bai reo u tnhdee d goeft h ec e lal r e
c o m p o cuinl idaan db e c a uosfteh e i r
s i zaer eb e sste eunn d eDrl C ,
(b)Thestichotrichcil
aleStylonychla
phase
aphed
under
nytlIusphologr
s fd e t a i l
c o n t r aNsot ,tteh el o s o
p a r t i c u laatrt h
l yea n t e r i(ot or pe) n do f
t h ec e ldl u teos w a m pbi nytgh eh a i o
B a r 1s 0 0p m
[,1
LtER
SGI\I
NICOLA
COURTISY
Physics Prize for the phasecontrast microscope which
allowed changesin phaseto
be made visible. Essentially
this is done by making the
light
passing through an
object interfere with light
passing through the background. This interference may be additive, causing a
brightening, or subtractive, causing a darkening in the
image. The cell may be alive and moving and otherwise
unstained. This technique is probably best used in
microbiology to observefine projections, such aseukaryotic
flagellawhich are exceedingly difficult to observein life by
BEL0WT
n labelled any other technique. The disadvantage ofphase contrast is
TheciliateDidiniun nasutu
a n tsi t u b u ltiang g ewdi t h
with
f l u o r e s ac n
ed
ipnh o i o g r a up nh de ed r the halo which it createsaround an object which can be so
eton bright asto obscuredetail.
UVlightThetubulininthecytoske
h a tsa k etnh el a b e l
a n di nt h ec i l i a
r e v e a tl ihnetgw og i r d l oe fsc i l l a n d
Interference contrast. Strictly, all microscopesform their
t h el o n g i t u doi nr gaaLzna t i oonft h e
i bt raiLlTs h e
c e lils1 4 0p m
c y t o s k e fl e
images through interference, but in the interference
long
microscope the optics are artanged so that the
contrast
[IUSEUX/
NAIURAT
HISTORY
SUE
|]OPE
COURTESY
interference is most sensitive to the rate of change of the
optical properties, hence the system is known asdifferential
interferencecontrast or DIC. The optical principle of this
However, Iike phase contrast, the halo generated by a
strongly fluorescent object can obscure more weakly
fluorescing objects nearby.Many fluorochromes also bleach
when they areexposedto UV light and so fluorescefor only a
very short time. The use of scanning high intensity light
sources,typically lasers,can help to overcomethis problem.
Depth of field
The problem of depth of field is faced by those who want to
observecomplete systems rather than thin sections. The
parts of the specimen which are out of focus exist as a diffuse
blur which detracts from the clarity of the in-focus image.
Holography. In principle it is possibleto take a holographic
image ofa drop of water which could then be re-createdby a
projector and studied using a conventional microscope. To
method was first describedin the late 1lth century byJamin
but it was the work ofNomarski in the 1950s that made the
our knowledge, there is no published record of this ever
technique easily available to,the biological laboratory.
DIC images are difficult to interpret becausethe effect of
a processofconvolution which cannot readily be reversedby
the interference is as though the specimen was obliquely
sizeof the calculations necessary.
illuminated creating a pseudo J-D appeannce.The contrast
effects are, however, demonstrating differences in the
Confocal microscopy. The new-kid-on-the-block
optical path properties, not the actual thickness. Real cells
do not often look like fried
eggs with
a protruding
having been done. The formation of the holographic plate is
computer becauseof the complexity and, particularly, the
the confocal microscope,which once again has its roots in
t h e 1 9 t h c e n t u r y .T h e t r u e m i c r o s c o p e i,. e . a n i n s t r u m e n t
capable of forming a real-time image, was patented by
Minsky in I95l andmechanical instruments were produced
nucleus.
a decadelater. In the late 1970s the advent of comparatively
Fluorescence.UV light was
low-cost digital computers and lasersmade the instruments
first used as a microscope
more widely available and by the early 1990s it was a
illumination sourcein 1904
practical proposition to havethem in biological laboratories.
by Kcihler, in an effort to
The principle of the confocal microscope is to use an
i m p r o v e s p a t i a l r e s o l u t i o n . optical stop, a small hole, at the objective'sprimary focus.
Instead, the far more use- The effect of this is to allow only in-focus light rays to pass
ful property of specrmen
through. To turn this pin-point into an image it has to be
fluorescencewas discovered.
scannedover the specimen. This takes real time, of course,
and renders the system of limited value to moving (live)
Like
E
$r$*trffi
#ffi e#tu#ffiYTODAYVOL26l MAY99
dark-field illumin-
ation, the fact that most
specimens. The removal of out-of-focus information from
materials do not fluoresce
the resulting image results in what is known as an optical
gready improves the ability
section and repeated sections can be built up within a
to study those that
computer into an effective solid model.
do.
FF
r.
li
I'
The loss of total light by the very small confocal aperture
has to be compensatedfor either by use of a photomultiplier
I
I
I
|
I
I
I
J
I
I
I
I
I
I
lr..
I
I
I
|
I
It
I
I
affordable video cameras in the 1980s brought a new A B O V E :
h ft h ec h r y s o m o n a d
technique to microscopy.The first video cameraswere based S w i m mpi nagt o
flagellateSpumeIlaeIongataillustrated
or by an enormousincreasein the intensity of illumination. on tube technology and were prone to a number ofproblems u s i ndgi g i tfai l mA
c o n v e n t ivoindaelo
Sfith very intense illumination it is necessaryto be able in terms of accuracyand resolution. These days tubes are c l i pw a sr e c o r duesdi nD
gI C
0 p t i cas
CCD
camera
anda U-[/latic
SPVIR.The
,o discriminate the illumination (background) from used only in specializedcircumstances.
c l i pw a sc o n v e ritnetdod i g i tfaol r m a t
.he interference pattern that is the image. This is done most
The charge-coupleddevice (CCD) is a semi-conductor u s i nagR a d i d
u isg i tfai l mc a r o
d na
h p u tSeirn, gflrea m e s
effectively by employing fluorescence to shift the wave- array which accumulates charge when a photo lands on one [ / I a c i n tco0sm
( d u r a t i1o/n2 5s )w e re x t r a c tf e
r odm
length of the light to be observed and to filter out the unit. These chargesare read off at a standard time and the
t h ed i g i t calli pasn da s s e m bi n
l et d
o
illumination source,exactly as in a standard fluorescence system is re-set for the next image. The data are run together a s i n g sl et i l l - i m af igl ee,
microscope. If the illumination source is suitably con- into a standard TV signal in most cameraswhich is passedto I h en u m b eornst h el e fgt i v teh et i m e
i ns e c o n d s / f r aBmaer ,sp5m
..ntrated, normally a focused laser,then only the region of a video recorder or a computer digitizer. In the latter case, COURTESY
GNOVARINO,
NAiURAt
HISTORY
]\4USEUII,l
tnstantaneousinterest is illuminated which considerably the digitizer board has to try and dismantle the signal back
r"ducesthe impact ofphoto-bleaching.
into the cell units of which it was first composed. One
Deconvolution. The combination of in-focus and out-offocus information is called convolution and is well defined
problem with CCD cameras is that the array accumulates
random signal as a result of thermal noise. This can be
mathematically. It is possible to achieve the confocal effect
*ith a normal microscope by reversing the process,which
considerably reduced, and the sensitivity of the camera
consequentially increased,by cooling the chip.
The tumbling price of fast personal compurers and large
.un be done ifyou have a sufficiently powerful computer and
you know a great deal about the optics of the instrumenr.
storagedeviceshas now opened the field ofdigital video asa
routine application in the laboratory to record and study
f n e l a t t e r i s s u ei s t h e r e a l s r u m b l i n g b l o c k . I n p r a c t i c e ,
dynamic processesunder the microscope.There have,asyet,
however, microscope images can be grearly improved by
been comparatively few published studies in microbiology
exploiting the potential of this technique.
a.convolution.
I
I
I
I
I
I
I
I
I
I
I
I
I'
I
I
I
I
I
I
I
I
I
|
I
I
I
I
I
I
I
I-
Timeand the movies
There is more on the collective mind of modern biologists
,han mere description: the recognition of the dynamic
of biological processesand interactions demands
"uture
systems capable of producing images of changing
powerful addition to the microscopist's arsenal. Apart from
deconvolution and work on 3-D images, there has been very
tpecimens. The halo effect in phase contrasr, for instance,
rather limits irs usefulnessin the caseof actively swimming
little progress in image analysis methods since the early
1980s. These techniques are, however, rather mathematical
nugellates,when DIC is a more appropriate choice. If the
and tend to be driven from the command line of a computer.
Few things seemto put biologists offmore effectively, so progressin computer-assisted microscopy has largely come with
..lls slow down then phasecontrast once again becomesthe
method ofchoice.
improvements in software design making it easierto use.
Cameras
The original microscopeswere intended to permit visual
Developments
observations.Film cameraswere added later ro allow the
imagesto be recorded, although anyone experiencedwirh a
It should, we hope, be clear from the above that very little
new physics has entered the field of microscopy since
microscopewill know that the information captured on film
is often only a fraction of that available down the eye-pieces.
the development of phase contrast. Nonetheless, today's
instruments will, in most but not all circumstances,outperform their turn-of-the-century equivalents.
The first constrainr is the amounr of light. Film
.-ulsions trade the amount of light neededto exposethem
the grain size,i.e. the resolution, ofthe photographic
It is in the field of technology, of new combinations
of known physics, chemistry and mathematics that
and processing,especiallyof colour emulsions, have greatly
microscopy is developing now. Since we srarted with a
clich6, we should end with onetoo-!0u ain't seennffin' yet!
"Sainst
i-age. Advancesin the chemistry of emulsion production
t.lieved this limitation. Nonetheless,for motile cells the
length of time needed for exposure inevitably leads to
motion-blur. The use of a flash tube is still the best way to
overcomethis problem, to deliver a high-intensity burst of
light of very short duration. Sadly few modern microscopes
are,or can be, equipped with flash tubes.
I
I
- Video
I
The amount of available light has been a limiting factor in
the use of cine film in microscopy, but the arrival of
I
I
r
lmageanalysis
Once you have adigital image, then many forms of image
processing are now possible and these techniques are a
O Dr Dave Robertsl and DrGianfranco Novarino2
work in the Department of Zoology at the Natural
HistoryMuseum,CromwellRoad,LondonSW7 58D
(FaxO171
9388754)
1Tel.017 1 938 8790;[email protected]
2Tel.017 1 93891 03;[email protected]
Furtherreading
The Royal Microscopical
Society (RMS) handbook series
is recommended, particularly
the titles listed below.
Bradbury, S. & Bracegirdle,
B. (1998). lntroduction to Li ght
M icrampy. MicroscopyHandbook
Series,)4 pp. Oxford: BIOS
Scientific Publishers, in
association with the RMS.
Bradbury, S. &Evennett, P.
(l 996). C ontra st Techni quesi n
Light Microscopy.Miroscopy
Handbook Series,1 18 pp. Oxford:
BIOS ScientificPublishers,in
associationwith the RMS.
call, J. c. (L996). Views of
the C ell. A P ictorial H istory.
American Society for Cell
Biology.
Sheppard, C. & Shotton, D.
G997 ). C onfocalLasa Scanning
M icrwnpy. Micros copyH andbook
Series,106 pp. Oxford: BIOS
Scientifi c Publishers, in
associationwith the RMS.
I
I
E
ffi#$#ffi
#ffi$ffi$"sffi roDAyvo L26ltvAy99r
Atom ic force m ictoscopy
AlastairSmith
The principleof the atomicforce microscope
Microscopeshavehistorically been tools ofgreat importance
in biological science.The atomic force microscope(AFM)
is one of a famlIy of scanning probe microscopes which
has grown steadily since the invention of the scanning
tunnelling microscope by
Binnig and Rohrer in the
early eighties for which
they received the Nobel
Pilze for Physics in 1986.
The AFM usesa cantilever,
usuallymade from silicon or
silicon nitride, with a very
low spring constant, on
the end of which a sharp
tip is fabricared using
therefore there is the potential for observing biological
processesin real time. Severalinstruments are commercially
available for around f 100K and in general the technology is
straightforward to useand occupiesonly a small table top.
O High resolutionimaging
There have been many studies of biological materials using
AFM in the few yearssince its conception, including nucleic
acids and their complexeswith proteins, two-dimensional
protein crystals and individual isolated proteins, membranesand membrane-bound proteins, and living cells.
One of the most extensively studied systems is nucleic
acids which have now been imaged with sufficient
resolution to measurethe pitch of the double helix. Nucleic
acids may be deposited on mica quite simply by using a
divalent cation to bridge between the negative backbone of
s e m i - c o n du c t o r p r o c e s s i n g the nucleic acid and the negatively charged mica surface.
techniques (Fig. 1). \When the tip is brought close to a Most recently there have been several reports of AFM
ABOVE:
ofatypical sample surfacethe forces between the tip and sample cause imaging of the complexes formed between proteins
micrograph
Fig. t. Electron
shown
cantilever
mode
AFIVI
tapping
the cantilever to bend and this motion can be detected and DNA which have, for example, provided detailed
iP
u p s i ddeo wtnor e v etahles h a rt P
p
m
B
a
r
1
0
0
f
o
r
i
m
a
g
i
n
g
used
optically by the deflection of a laserbeam which is reflected information about the changesin conformation of DNA in
VIECO
ENTS,
DIGITAL
1NSIRUI\,1
COURIESY
offthe back ofthe cantilever.Ifthe tip is scannedover the responseto protein binding. The one-dimensional diffusion
GROUP
IlIETROTOGY
sample surfacethen the deflection of the cantilever can be of RNA polymerase along DNA has been imaged in real
T OR
PI G H T :
recorded as an image, which in its simplest form represents time and the enzyme was seento slide along DNA and even
ofa
AF[,4
image
Fig.l. [tlagnetic
the three-dimensional shapeof the sample surface.Many hop to neighbouring nucleic acids on the substrate surface.
g a r nfei ltms h o w ifnl ogw e r - l i k e
variants now exist which use special tips to probe the Fig. 4 shows one recent example of AFM imaging of a
m a g n edtoi cm a i n s ,
VEECO
NSTRII/ENTS,
DIGITAL
COURTESY
electric, magnetic (Figs 2 and 3) or thermal properties of protein/DNA complex. Tapping mode AFM has been used
VFRATETLO
AND
GROUP
IIFTROTOGY
to image an individual complex of human transcription
surfaces,and even optical spectroscopyis now possible with
BELOW:
about 50 nm lateral resolution using scanned probe
ofa
AF[4
image
ilig.ft.Magnetic
techniques.
permanent
praseodymium-iron-boron
The resolution of AFM dependsmainly on the sharpness
magnet,
VEECO
INSTRUI\nENTS.
DGTAL
COURTISY
of the tip which can currently be manufactured with an end
AND
R.STRITT
GROUP.
[IETROLOGY
radius of a few nanometres. Atomic resolution is easily
obtained on relatively rolust and periodic samples. Soft
sampleshowever, particularly biological samples,provide a
more difficult surfaceto image becausethe forcesexerted by
the tip during imaging can causedeformation of the sample'
The problems involved with imaging soft samples have
been overcome to a large extent by the introduction of
tapping mode AFM imaging. Instead of maintaining a
constant tip-sample distance of a nanometre or so, the
cantilever is oscillated in a direction normal to the sample
resulting in only intermittent contact with the surface.This
greatly reducesthe lateral forcesbeing applied in the plane
of the sample which are responsiblefor most of the damage
asthe tip is scanned.The AFM is capableof better than 1 nm
lateralresolution on ideal samplesand of 0'01 nm resolution
in height measurement.
It appears that a protein-protein
interaction has facilitated looping of the DNA to allow two
distal DNA sites to be brought together on the substrate. A
factor 2 with DNA.
goal of someworkers is to develop AFM imaging techniques
to a point where the DNA sequencecan be read; however,
this ambitious goal remains elusive.
The highest resolution images are obtained on tightly
packed structures such as two-dimensional arrays of
proteins becausethe packing affords a greater mechanical
stability to withstand the imaging forces.In casessuch as
this the resolution of the images is better than 1 nm because
the highly regular assembly of proteins also allows
averaging to be performed which greatly improves the
signal-to-noise ratio. The quality of information in such
images has been demonstrated by Engel and co-workers
who have reported real-time observation of the central pore
of proteins in the HPI layer of Deinococcusradiodurans
opening and closing. Another example, shown in Fig. 5, is
the molecular resolution tapping mode AFM image of the
periplasmic surface of OmpF porin from Escbericbiacoli
There are some significant advantages of AFM as an
imaging tool in biology when compared with complimentary techniques such as electron microscopy. Not only
doesAFM achievemolecular resolution but the technique
taken in buffered solution. A rectangular unit cell arrangement(a = I35 A, b = 82 A) c^n be seeneachcontaining two
porin trimers with a lateral resolution of about B A.
requires almost no sample preparation and, most
importantly, can be performed under fluids, permitting
cell surfaceis extremely soft despite the structural support of
the cytoskeleton. Obviously deformation of the sample
samplesto be imaged in near native conditions. The fluid
may be exchanged or modified during imaging and
during imaging can seriously limit the resolution which can
be achievedon cells and although the overall shapecan be
ffi &ffi
ffisffi effih#ffiYroDAYVOL26/MAY99
Imaging of living cells is not straightforward becausethe
measuredeasily,surfacedetail is difficult to obtain. In some
casesthe nucleus can be cleaily seen in the images, which
suggests that it is less easily deformed than the cell membrane, and movement of the actin filament bundles beneath
the periphery of the cell membrane has been observed.
Measurement of biolog icaI i nteraction forces
In addition to the porential of the AFM to provide very high
resolution images of biological samples and to monitor
molecules has been observed by several groups and
measured to be of the order of a few hundred piconewtons.
The resolution of the AFM as a force or binding strength
measuring device is of the order of about 10 piconewtons,
limited by the thermal noise of the cantilever at room
temperatufe. An exquisite example of the measurement of
such biomolecular interactions was reporred by Lee and coworkers at the Naval Research Labs in \Washington. Two
complimentary DNA oligonucleotides, one tethered to the
conformational changesand biomolecular processesin real tip and one to a gold substrate,were allowed
to interact and
time under native conditions, rhe instrument is also capable then pulled apart whilst the forces required
to rupture the
of manipulating molecules and measuring the strength of double helix conformation were measured.
biomolecular interactions with piconewton sensirivity.
Perhaps one of the most exciting demonstrations of the
The forcesexerted between the silicon nitride tip and the potential of the AFM to measurebiomolecular
interactions
sample arise principally from van der \Waal'sinteractions. has been the recent demonstration by Gaub's
group, and
These interactions arc rathet non-specific in the biological others, of the mechanical unfolding
ofsingle proteins. Gaub
sensebut lead to bending of the cantilever which provides has shown that the forcesrequired to unfold
the subdomains
the topographical information for the images. However, it
of titin, the giant muscle protein, can be measuredby AFM.
is relatively straightforward to modify the tip surface In theseexperiments the AFM tip is used
to pick up part of
chemically so rhat its interaction with the sample may be the vast titin molecule whilst the rest remains
absorbedto a
made highly specific. For example the tip may be modified gold substrate. The tip is then withdrawn
and a seriesof
to havea charged surface,one which readily forms hydrogen small tugs on the cantilever can be observed
which have
bonds or may be made very hydrophobic. In these simple been attributed to the unfolding of the immunoglobulin
casesit is the interaction with the sample which bends the and fibronectin domains. The forcesmeasured
are in two
cantilever and therefore the information that is contained phases.First, the extension ofunfolded
chains which appear
in the images has chemical information about the tipto fit well to a worm-like chain model and second, a
sample interaction. Tip
dramatic step which is identified with the catastrophic
.
modification
is usually unfolding of a domain. This type of measurement, which
achieved using the well has initiated a flurry of activity in mechanically manipuknown processof thiol self- lating biomolecules, is only the first step in a developing
assemblyon gold. The rip is new field ofbiophysics basedonAFM technology.
first coated with a thin layer
ofgold by evaporation, then
ABOVE;
F i g "$ . l m a goeft h ep e r i p l a s m i c
surfao
ce
f0 m ppFo r ifnr o n[ . c o l i ,
COURTTSY
DIGITAI
INSTRUI\,lENTS.
VEECO
I/ETROLOGY
GROUP,
AND
A,ENGEL
Thefuture
immersed in a solution of
rrr-functionalized alkyl thioi
The fact that AFM is relatively cheap technology and
straightforward to use suggests that it will be accepted
molecules. These molecules
have a functional head group
which will provide the tip
quickly as animagingtool in biology. The ability to perform
real-time observations of biological processesunder natiye
conditions will be ofgreat inrerest and asthe biochemistry is
with the desired physico-
developed to modify tips in more complex ways to attach
COURTESY
DIGITAT
JNSTRUIIIE|\]TS,
VTECO
CROUP,
AND
proteins, peptides and small organic molecules, then the MEIROTOGY
C,BUSTAI\IAN]E
detailed measurement of biomolecular interactions appears
chemical properry and an
alkyl chain spacerof about 10 carbons terminated with a
thiol group. The sulphur sponraneouslyforms a covalent
bond with the gold coating on the tip and the molecules
pack tightly to form a well ordered monolayer with the
functional group uppermost, creating a new surface of
LEFT:
Fig.,5.Tapping
mode
AFM
image
ofanindividual
complex
ofhuman
transcriptmn
factor
2withDNA
to be an areawith very great potential. The simplicity of
the instrument also lends itself to integration with other
instruments. In the author's laboratory, as in severalothers,
tailor-madechemistry on the tip.
AFM is being combined with laser spectroscopyso that
mechanically induced conformational changescan be moni-
Tips may also be modified to have biological functionality. For example, antibodies can be tethered to the tip
via flexible polyethylene glycol spacers,permitting the
antibody to bind to an antigen on a sample surface. Using
tored by fluorescenceor infra-red specrroscopy.It seemsthat
AFM is likely to become one of the most widely used high
resolution microscopy techniques in the biological sciences.
such a tip, the distribution of antigens over a cell or other
surfacemay be mapped, but it is also possible to pull the
O Dr Alastair Smith is a lecturer in the Department
of Physics and Astronomy atthe lJniversity of Leeds.
antibody-antigen complex apart by moving the tip away
from the substrate on which the antigen is absorbed
and measurethe strength of the interaction directly. The
binding event between single pairs of streptavidin/biotin
His current research is focusing on the application of
laser spectroscopy and scanning probe microscopy
to the study of biomolecular structure and dynamics.
e- m ai I d.a. m.s m ith @leed s.ac. u k
Furtherreading
Bookmark the following
web sites:
http://www.di.com
http ://www.thermomicro.com
http://www.molec.com
ffi $ffiffi&ffi s#e.#ffivroDAyvo L26lMAy99 E
mrcroscopyl
taking backthe knight
Fuller
Stephen
Vitrified samples
Whycryo-EM?
An instructor in an introduction to an X-ray crystallography course some years ago explained the difference
between electron microscopy and X-ray diffraction as
structural techniques. Imagine, he said, setting out to
determine the structure of a man. One approachwould be to
cover him in a suit of armour, place him in a vacuum until all
the water is gone and broil him under a high energy beam
until the armour began to melt and flatten, and finally take
a picture of the remnants and call it the structure. That, he
said, is the electron microscopist's approach. The X-ray
crystallographer, in contrast, maintains his sample in an
aqueous environment and determines the stfucture of the
entire sample in three dimensions rather than only that of a
shell of a metal shadow or a heavy metal stain. From such a
perspective, the choice between the two techniques was an
BELOW:
c rno g r aopfh s obvious one to any seriousstudent ofstructure.
F i g .1 "C r y o - e l e cmt ri o
takenona PhilipsC[/200equipped
SFV
Today the situation has changed dramatically and few
e m i s s igounna t2 ! m
af i e l d
with
) d e r f o c u s ,structural biologists would omit electron microscopy as
( u p p earr)d4 p m( l o w eur n
virionssit ina layer
The700Adiameter
part of their characterization of a biological system. The
oe
ve
dt rh e
o fv i t r i f iw
e da t esru s p e n d
advent of cryo-electron microscopy (cryo-EM) has allowed
h o l eosfa c a r b of inl mT h ep h a s e
r eft h ei m a gcea u s e s the observation of biological samples in a layer of vitrified
c o n t r ansatt u o
t osb e
d i f f e r er e
n st o l u tri ao n g e
water. This avoids the drying associatedwith classical
a c c e n t u a tdeidf f e r ednetf o c u s e s ,
approaches.The use ofphase contrast to image the specimen
FULLER
STFPI]EN
COURTESY
allows one to perform unstained microscopy so that
the entire density of the
specimen contributes to the
The preparation of a sample for cryo-EM takes advantage of
the properties of water. \When water is cooled slowly (a few
degreesper second)it forms hexagonal crystals of ice, the
form found in ice cubes and snow flakes. Very rapid cooling
(thousands of degrees per second) traps the water in a
vitrified state in which the structure has not been allowed to
rcarrangeinto a crystalline form. Practically, this is usually
accomplished by a method developed 20 yearc ago by
Jacques Dubochet and collaborators at the European
Molecular Biology Laboratory (EMBL). A small aliquot
of the sample in suspension is placed on a holey carbon
film blotted to generate alayer of - 1000 A thickness and
plunged into a bath ofethane slush held in a container of
liquid nitrogen. Ethane is a very efficient cryogen since.
unlike nitrogen, it does not boil at the temperatures used
for vitrification. Nitrogen is not used directly since the
formation of gas around the specimen when it is introduced
into liquid nitrogen slows the cooling and leads to the
formation of ice.
The vitrified state is not an equilibrium one but rather a
metastable one. It can be maintained at liquid nitrogen
temperatures for long periods. Our group has examined
specimensstored in liquid nitrogen for more than 10 years
without loss of the vitrified state. Raising the temperature
above about -140"C causes devitrification and the
formation of cubic ice. Paradoxically,vitrified water freezes
upon warming. Cooling the sample again does not restore
the vitrified state, it simply generates cooler ice. The
vitrified sample is transferred to the microscope by passing
so that the contrast ofthese it rapidly between baths of liquid nitrogen and then
images can be accentuated mounting it in a liquid-nitrogen-cooled specimen holder
and the three-dimensional which is inserted into the microscope. Other schemes
image. Image processing
techniques have developed
structure determined by
combining the projected
have been used for generating vitrified specimens. The
requirements are sufficiently rapid cooling to avoid the
densities iri the individual
micrographs. Finally, mea-
formation of ice and maintenance of the vitrified state by
keeping it at low temperature at all times, usually by storage
suresof the reliability of the
resultant structures have
been developed and vali-
in liquid nitrogen.
dated by comparing them
with
structures
derived
from X-ray diffraction of the
same complexes. This has
led to the use of a divide
and conquer approach to
many systems. First, the
atomic resolution stfuctures
of subcomponents of a
macromolecular
complex
are determined by either
X-ray crystallography or
to provide a context for
is
used
Then,
cryo-EM
NMR.
these structures by showing their placement in the
complex and indicating where the structure must be
altered during assembly.
E
ffi $#ffi#ffi$#fu#ffiYIODAYVOL26l MAY99
The requirement for very rapid cooling is a limitation
of the technique. The method works best with specimens,
such as suspensionsof viruses or protein complexes, which
can be made very thin so that cooling is rapid. Thicker
objects such as cells must be handled differently and
represent a challenge to the field. Suspensionsamples also
present problems if they contain solutes which interfere
with vitrification. Samplescontaining salt or sucroseshow a
phasepartitioning after vitrification. Crystalline specimens
are usually handled in a somewhat different way. These
samples are often placed on a continuous carbon film in
glucose or tannic acid and cooled directly in liquid nitrogen
or in the holder rather than using ethaneasa cryogen. This is
possible becausevery high concentrations ofthese sugars
act asa cryoprotectant and inhibit ice formation.
The vitrified sample is typically maintained at near
-170'C during microscopy. The specimen is extremely
sensitive to radiation damage from the electron beam of
IF
differencesbetween separateparticle images reflects the
changein orientation rather than sample variation.
Three-dimensional reconsrrucrions of particles with
higher symmetry, such as icosahedralviruses, are particularly well developed.Building on algorithms formulated
by R.A. Crowther (MRC Laboratory of Molecular Biology,
Cambridge), a number of groups have developed methods
for treating the caseof icosahedralparticles. More than 150
LEFTI
iiil. I Three-dimensional
g e n e r aftreodm
r e c o n s t r uo
c tfSi oFnV
e a g se us c ah st h 0 s e
1 00 0 0p a r t i ci lm
r or f i loefs
s e einnF i g1 T h e
t r i a n g upl a
t h es p i k easr es e ear lsw e lal st h et h i n
p r o t esi n
h e ew
t sh i cohv e r lt ihee
m e m b r aonft h
e ev i r u s .
COURTESY
FIJTLER
SIEPHEN
such structures have aheadybeenpublished and the number
continues to grow. The use of a highly symmetric particle
allows the symmetry ro serveas a guide in determining the
orientation and makes the process of computing the
structure itself much more efficienr. Tesrsfor symmetry in
the particle images allows identification of thoseparticles in
the microscope. An image of an undamaged specimen is
obtained by using low dosetechniques.The specimen is first
imaged at low magnification so that areasof interest can be
i d e n t i f i e d w i t h m i n i m a l i r r a d i a t i o n ( < 0 . 1 e l e c r r o n sA 2 ; .
The image is then captured at higher magnification with
the first electrons to hit the specimen. Typically, the image
is formed with a dose of 5-10 electro.rt A-2. \Work with
crystalline specimensat -17 0 oC indicates that this dose
doesnot damage the structure at resolutions coafserthan
104.
the population which have been distorted and hence would
blur the reconstruction if they were included in the average.
Reconstruction methods have also been developed for nonsymmetric particles particularly by the groups of M. van
Heel (London) and J. Frank (Albany, USA). The power of
these methods has recently been demonstrated by high
resolution reconstructions of the ribosome.
Cryo-EMcomes of age
Cryo-EM
The images obtained by cryo-EM show details of the
entire specimen.In contrast to negative staining or metal
shadowing which show the surface of the sample, as the
and three-dimensional reconsrruction are
undergoing a renaissance.A few years ago, the best
icosahedralreconstructions achieved resolutions of slightly
armour models the features of the knight, the image is a
better than 304. Higher resolution was the domain of
electron crystallographersand others working with ordered
superimposition of all of the density in the sample. Inter-
specimenssuch ashelices.Two developmenrshave been key
preting such a projected image requires either restricting
in bringing a new exciremenr to the field. The first is the
establishment of methods for processing large numbers
oneself to the edges of the object or accounting for the
projected nature of the
image. Three-dimensional
reconstruction techniques take advantage ofthe fact that.
the image is a projection. The most powerful approach is
that of electron crystallography.However this can only bd
applied when the specimen is co-operative enough or the
investigator inventive enough to produce the sample in an
ordered two-dimensional crystal. The simplest of the
alternative approachestakes advantage of the homogeneity
of the specimen. A field of particles such as the one of
Semliki Forestvirus (SFV) shown in Fig. 1 can be viewed
either asimagesof separateparticles or asimages of the same
structure from a variety oforientations. The latter is key to
determining the
structure. The
process of
three-
dimensional reconstruction involves identifying
the
of images and combining them to produce a threedimensional structure. Combining thousandsof particles
enhances the relatively low signal to noise ratio in the
unstained, low doseimage of a single particle. The second
development is instrumental. The use of high voltage and
field emission gun sourceshas increasedthe strength of the
high resolution information transferred from the specimen
to the film. This is a consequenceof the fact that the image of
a thin unstained specimenis dominated by phasecontrast. A
more coherent electron source produces a better phase
image. The effect is particularly important for images of
single particles. Accurate determination of orientations
requires refinement against high resolution information
which is, in turn, necessaryfor enhancing the signal to noise
orientationsofeach ofthe views representedby the particle
ratio at hi gh resolution.
images and then combining these images to determine
the structure (Fig. 2). Obviously, the reliability of the
The determination of rhe fold of the hepatitis B capsid
protein by the groups of R.A. Crowther (MRC, Cambridge)
and A. Steven (NIH, Bethesda, USA) from the icosahedral
assignment of the orientation and the resolution of
the information contained in the image limit the final
resolutionof the structure. A pfocessof refinement allows
one to determine the orientations to higher reliability;
howeverthis processis only effective if the resolution of the
data allows determination of the orientations with high
precision.The homogeneity of the sample is critical to this
process.The reconstruction method assumes that the
reconstruction of hepatitis B coressignalled a coming of
age in the field. The methods used by the two groups
exemplified the two developments described above. The
Cambridge group used thousands of images raken on a
microscope equipped with a field emission gun source to
p r o d u c e a 7 ' 6 A r e s o l u t i o n r e c o n s t r u c r i o nw h i c h a l l o w e d
visualization of the cr-helicesof the structure. Srnce this
$f$$#ffi
#ffi $#r#ffiy ToDAyvoL 26lMAy99 E
marvellous demonstration of the potential of the methods, a
number of groups have applied this approach successfully
to larger systems. $7ork by W. Chiu's group (Baylor,
of independent hemispherical sectorswith closely packed,
ndially arranged Gag protein under the membrane with
Houston, USA) on herpesvirus and our group on SFV (Fig.
2) haveproduced structures at better than 10 A resolution in
particles do not all have the same structure and hence
which secondarystructure can be identified. This progressis
not limited to icosahedrally symmetric structures. The
averaging of images cannot make use of this basic property.
Approaching such a system requires a continual interaction
between biochemists and structural biologists to prepare
work on the ribosome mentioned above has now reached
resolutions of B Aand is serving to map out the changesin
conformation with the functional stateof the system.
The increasedresolution and demonstrable reliability of
homogeneous subassemblies such as the helical tubes
formed by segments of the Gag protein. It also will require
the information provided by the combination of cryo-EM
and image reconstruction have altered the gentle rivalry
unique structures of individual particles.
which once existed between X-ray crystallographersand
electron microscopists into a respectful working relation-
Although methods are still under development, current
ship. Three-dimensional structures derived from cryo-EM
not only provide context for the higher resolution structures
they can be applied in investigating a very broad range of
of components but are also increasingly used to investigate
large macromolecular complexes by crystallography. The
methodological developments such as the improvement of
techniques for cryo-EM tomography to determine the
The future of the technique remains full of promise.
techniques have reached such a level ofsophistication that
biological problems. No longer arewe restricted to working
on the best behaved systems. Cryo-EM has passed from
being a tool ofthe specialist to being an essentialtool ofthe
determination of the structure of the bluetongue virus core
by D. Stuart's group (Oxford) (seep. 59) utilized a threedimensional reconstruction from B. Prasad (Baylor,
microbiologist.
Houston, USA) to generate the initial model used for
phasing. The progress on the crystallography of the
Structural Biology Programme at EM BL, Postfach
10.2209, Meyerhofstrasse7, 691 17 Heidelberg,
G ermany (e-mai|: stephen.fuIIer @em bl -h eidelberg.de).
Hisgroup focuseson the use of cryo-EM and
three-dimensional image reco nstruction for the
study of enveloped viruses,membrane fusion and the
microtubule cytoskeleton as well as cell biological
techniques for the study of ER-Golgi transport.
ribosome has been aided by the use of reconstructions to
serve as an initial phasing model and a control for heavy
atom phasing at higher resolution.
Thefuture: promisesand challenges
Cryo-EM also provides resolution in time. The vitrification
method can be adapted to capture intermediates. The
approach dependsboth on the timescale and the system but
alarge range of conditions is accessible.\We employed a
simple spray technique in which the blotted grid was
exposedto a mist of low pH while it was plunging towards
the ethane bath to examine the structures formed by the
SFV spike during the first 50 ms after exposureto low pH.
At this early stage, the virion remains icosahedrally
symmetric and hence a three-dimensional reconstruction
could be performed by standard methods. Simple mixing
experiments have allowed us to examine the slower
interaction of the pH-activated virion with the target
the structure does not remain
vesicle. Naturally,
symmetrical upon contact and hence other approaches
must be used to determine three-dimensional structure.
Despite the recent progress,challengesstill remain. A
typical example is shown in the image of immature HIV
(Fig. 3). HIV is an ideal casefor'divide and conquer' since
RG
IHT:
f i g . $ "C r y o - e l e cmt ri corno g r a p h s
byinfected
HIVproduced
ofimmature
ofprotease
inthepresence
cells
oteins,
i n h i b i t oTrhse. n v e l oppr e
radial
ofthelipidbilayer,
features
d i s p o s io
t ifot hneG apgr o t eai n d
end
h e t e r o g e innepiat yr t i csliez a
s h a paer ee a s isl ye e n ,
FULTER
COURTESY
STEPHEN
defects in the packing between the sectors. Second, the
the structures of parts of all the structural proteins are
now known. This image contains a wealth of information.
It shows the layer of spikes on the surface, features
within the membrane itself and the radial arrangement of
the independently folded domains of Gag. It shows two
other key features which represent challenges for the
determination of the three-dimensional structure. First, the
particles are not icosahedral.Rather they seemto be formed
E mcnoFloHlwroDAYVoL2o/MAYgg
O Dr Stephen Fuller isa SeniorScientist
in the
-_
I
Grystallographyand the atomic
anatomyof viruses
David
l.Stu?rt,Jonathan
M,Grimes,
NickBurroughs
& PeterP C,Mertens
David Baltimore in his 1976 Nobel Lecture
observed "The study of biologyis partly an exercise
in
natural aestbetics,\X/ederiuemucb of our ileasure as
millilitre, is simply treated as if it were a small protein and
subjected to the battery ofcrystallization techniques now
pet down to the details of all of its
becaase
be can seeinto bis cbosen
m.olecules.
Tbe uirologist seesbow an extremeparasite fanctions
usingjust tbemostfandamentalasputsof biologicalbebauiour..."
Naturally, since viruses are large, the diffraction from virus
crystals is far weaker than for single proteins. For insrance,
standardizedin commercial kits. Whilst it is perhaps not
biologistsfron tbe continaing reahzation of how economica/,e/egant surprising that robust spherical virions crystallize, it is
and intelligent are tbe accidentsof euolutionthat baaebeenmain- astonishing that the crystals, held together by only a few
tained by selection.A uirologist is amongsttbe luckiest of biologists flimsy non-covalent interactions, are so beautifully ordered.
These words are made flesh by X-ray crystallography. \7e
use relatively soft X-rays (wavelength about 0.1 nm) that
in the caseof the bluetongue virus crystals we have looked
at, the number of repeating unirs acrossthe width of the Xray beam hasbeenassmall as300, dramatically reducing the
shine through our small crystals of virions, illuminating
amplification of the signal upon which the method rests.
every detail and allowing atomic models to be constructed For this reason,and becausethe number of diffracted beams
'spherical'
of the exquisitely ordered symmetrical shells of
to be measuredincreasesin proportion to the particle size,
viruses.Knowledge of the three-dimensional positions of virus crystallography still presentstechnical challengesand
the atoms gives a complete static view of the virus and progresshas been quite closely linked to the development of
crystallography can, via the somewhat obscure B-factor,
indicate molecular flexibility. The results are objective,
however, the personal aestheticsofthe crystallographer are
betrayed in the often riotous choice of colours for their
representation.The first virus scrucrure was determined in
intense X-ray beamlines at synchrotrons. Several third
generation synchrotrons are now coming on-line around the
world (the first of which was the European Synchrotron
Radiation Facility at Grenoble; Fig. 1) which present new
1977 by Stephen Harrison and co-workers at Harvard, and
over the yearc a handful ofgroups around the world have
opportunities to structural virologists. These machines
produce X-ray beams thousands of times stronger than
can be obtained with conventional X-ray generators and
built up a gallery ofover two dozen virion strucrures that
cover hosts ranging from bacteria, through plants, to
allow the accuratemeasurement ofvery weak data. Furthermore, undulator beamlines are available on these machines
animal's.The structures almost exclusively relate to nonenvelopedspherical viruses and a challenge for the future is to
which produce very nearly parallel beams,allowing more
reflections to be resolvedon a detector ofa certain size.\With
extend the technique to the lessamenable lipid-containing
viruses and the beautiful but complex machinery of some
the technology now available it is hard to seethe limit to
what can be achieved.For instance, we have recently solved
bacteriophages.Crystal structures provide snapshotsof the
virus life cycle which have profound implications for our
thoughts on many aspectsof their biology. Thus structure
the structure of the bluetongue virus core that contains
almost 1000 polypeptide chains (Fig. 2). Even larger
structures could be analysed,provided that they have a well
hasbegun to at least partially illuminate questions of virus
defined structure and provided there are dedicated micro-
assembly, evasion of the immune response and cell
recognition and entry. \Thilst crystallography has ledto
biologists committed to making the many milligrams of
pure virus required to analysesuch complex systems.
some unexpected simplifications in our thinking about
viruses(for instance, a recurring structural motif suggests
that most viruses studied to date may be related), it has also
shown the tremendous richness of invention that has been
achievedby selecting accidentsofevolution.
Small crystals/ large viruses
A crystal of an organic compound or small protein contains
many trillions of identical molecules whose molecular
Problemspots
X-rays cannot be focusedsufficiently well to directly image
atomic structures. Instead the information in the beams of
scattered X-rays is reconstructed with a computer to
provide the image. The diffraction pattern obrained is a
seriesof spots which may be thought of as representing the
scattering from the virus viewed through a grating. The
structure may be visualized by amplifying the feeble
periodicity of these spots simply reflects the periodicity of
the crystal whereas the brightness of the spots reflects the
scatteringof a single molecule. Thus, when illuminated by a
nearly parallel beam of monochromatic X-rays, all the
distribution of electrons within the virus. To solve a crystal
structure diffraction spots afe recorded from a complete set
moleculesin the crystal scattertogether in certain directions
to give detectablediffracted beams.The concentration of
of views of the crystal. Since X-rays quickly damage virus
crystals we usually need to add together data obtained from
the signal into such diffraction spots, according to rules put
many crystals. Next the spots must be transformed into a
map of the electron distribution in the virus. Here we
forward by Bragg, allows relatively simple compounds to be
analysedquite routinely in the lab. Virus crystallography is
somewhatmore complex but identical in its essentials.It
turns out that the necessafyfirst step, that of growing
encounter a fundamental problem. The map is constructed
from many componenr waves of different frequencies,
amplitudes and directions (any objecr can be representedin
crystals,is often relatively easyforviruses. A solution ofpure
virus particles, at a concentrarion of a few milligrams per
this way, as pointed out by Fourier). Each diffraction spot
definesone such componenr, whose frequency and direction
ffi trffiffiffiffi$#tuffiffiY
IODAY VOL26/MAY99E
Earlyachievements
The seeming complexity of
virus capsids can mask their
underlying simplicity. In
1955 \Tatson and Crick
realised that 60 identical
subunits could self-assemble
to form a closed particle
with icosahedral symmetry,
is describedby the direction ofscatter ofthe diffracted beam
AB
OVE:
Synchrotron and whose amplitude correspondsto the spot brightness.
IheEuropean
Fig.'$.
The
Facilily
atGrenoble
Radiation
virus
c'ystal To put the waves together to form the image we need to
abluetongue
beamline,
pattern
in know their relative phases(this is crucial - in-phase waves
areshown
anditsdiffractlan
p,
clos
e-u
out-of-phase wavesinterferel).
DSTUARI
PRODUCED
BYJ GRIiVES&
O P P OPSAI TGEE :
of
structure
ofthecore
$:ig.fl.The
dsRNA
virusThecoiled
bluetongue
genome
bytwo
surrounded
isshown
have
been
which
layers
ofprotein
partially
away
forclarity
siripped
augment each other whereas
Unfortunately, when a diffracted beam hits a detector, only
its energy is recorded and all phase information is lost. The
crystallographer hasto find another sourceof information to
reconstruct thesemissing phases.Fortunately, there are now
routine techniques which, for viruses, usually start from
rough phase estimates derived from a three-dimensional
&DST!ART
BYJ,DIPROSE
J GRI[,,IES
PRODUCED
PREPARID
BYR,TSNOUF
SOFTWARE
USING
model. The model might be a crystal structure of a related
virus, a lower resolution cryo-EM reconstruction or perhaps
a combination of electron microscopy and high resolution
X-ray structures of individual protein components.
Symmetrysavestheday
thereby satisfying the biological imperative of genetic
efficiency. Some yearslater Casper and Klug proposed that
even more complex assembliesmight be made by relaxing
the requirement for exact symmetry (giving rise to the term
'quasi-equivalence').
This can be achieved by breaking the
icosahedralbuilding block down into a number (T) of subtriangles, such that the shell is made up of 607 chemically
identical units. This explains the architecture of many
viruses but does not provide a mechanism by which the
exact size of such massiveassembliesis determined. This is
exemplified by tomato bushy stunt virus (TBSV, the first
virus solved), where the 7 = 3 arrangement of the protein
building blocks is exactly as predicted by Casper and Klug
but where the architecture is defined by a pathway of
controlled conformational switching of the chemically
identical subunits during assembly.This combination of
quasi-equivalence and conformational switching has now
been found in many virus structures. The TBSV structure
The phasesdepend on the orientation and position ofthe
model with respectto the axesof the crystal. The icosahedral also revealeda new type of protein fold, an elongated wedge
symmetry of the virus provides us with a key not only to made from long strands of p-structure, often called a jelly
unlock these secretsbut also to refine our rough initial estimates of the phases.Icosahedralsymmetry consistsofa set of
5-,3- and 2-fold symmetry axesarranged in an absolutely
fixed relationship to each other. If we look along a 5-fold
symmetry axis, the virus structure will repeat every 36015=
J2" around the axis. The sameis true of the scattering from
the virus. It is a simple mattef, in a computer, to searchfor
such repeatsin the measuredscattering and thereby lock on
name. This structure has now becomeavirtual trademark of
viruses, being found in the capsid proteins of an enormous
range of viruses (although it is relatively scarce in the
proteins ofbacteria, plants and animals). The tempting (but
unproven) inference is that this revealsunsuspectedancient
Iinks between plant and animal, RNA and DNA, and
to the orientation of the particle. Once correctly orientated
the model is moved systematically around the repeating
volume of the crystal to find the position that best predicts
enveloped and non-enveloped viruses. Even ifthis is true it
remains a complete mystery why this structural signature is
the observed scattering. Phasesmay now be calculated,
combined with the measured spot amplitudes, and an
very different structural contexts. Very different questions
were answeredwhen the first animal viruses were solved in
electron density map calculated. This map will be biased
towards our rough model of the structure, adding noise to
virus by Michael Rossmann. These structures immediately
the image. Again icosahedralsymmetry helps us, since the
repeating crystal lattice cannot build in the icosahedral 5-
properties of animal viruses and to an apparent resolution of
fold symmetry. Inescapably,therefore, the virus particle has
additional internal symmetry. Since we have located these
symmetry axesit is a simple matter to impose icosahedral
symmetry to clean up the picture. In practice we use a cyclic
procedure, using the cleaned up image to get better
phase estimates, which are combined with experimental
amplitude measurements to give a new, improved image
which is then subjected to further sanitization. Fortunately
computers are not easily bored and carry this process
through many cyclesto produce maps ofgreat clarity.
E
roll since its strands are wrapped up as if the chain had been
formed in the same way as the American confection of that
ffi$ffiffi#ffi8#fu#ffiYIODAYVOL26/MAY99
maintained over such enormous evolutionary distance in
the mid-S0s; poliovirus byJim Hogle and human rhinoled to a clear rationalization of many of the antigenic
the conundrum of how viruses maintain binding sites for a
cellular receptor whilst evading the immune response.The
canyon hypothesis proposesthat receptor binding residues
are concealedfrom antibody molecules within a crevice on
the viral surfaceand is still the subject of much discussion.
Movingup a gear:bluetonguevirus
Most virusesanalysedcrystallographically have been around
30 nm in diameter. The publication last year of the structure
of the 70 nm bluetongue virus (BTV) core particle (FtS.2)
T
demonstrates that much larger assemblies can now be
tackled. BTV is a representativedsRNA virus and belongs
processof crystallization has laid down viruses in random
orientations, blurring the image beyond recognition. The
to the most populous family of such viruses, the Reouiridae. BTV core is
very unusual in this respect and we can get a
The coresof theseviruses acr as rranscriptional machines in fair idea of how
much of the genome (20,000bp), made
infected cells, holding their genome and rranscriptional up of ten unequal
segments, is arranged. Unfortunately
enzymeswithin a prorecrive shell so that dsRNA is never inappropriate blurring
of the image limits the detail and
revealed ro the infected cell, eliminating any chance of a means that interpretarions
are speculative.Nevertheless,by
cellular response(such as the interferon response)to this taking rhe structure
together with information from
unusual nucleic acid. The strucrure suggesrsa compelling
previous electron microscopical and biochemical analyses
hypothesisfor the assemblyof nearly l00O protein subunits. we can propose
a working model in which the enzymesform
The core is made from two principal protein componenrs. transcription
complexes under each of the 5_fold apices of
There is a thin skin covering the genome and enzymes,made the protein shell.
These contain three components, which
froml20 copiesof alargeproteinyp3(72), which assembles (working ourwards
from the centre) unwind the genomic
into an icosahedral arrangement via conformational dsRNA (a
NTP-driven helicase),transcribe a messenger
switching to yield a partern of subunits nor seenin other RNA sensecopy and
cap it before it emergesfrom the core,
viruses and not predicted by the theory of Casperand Klug.
ready to initiate protein synthesis. \7e suspect that the ten
This is clothed in 780 copiesof the protein Vp7(Tl3) in an RNA segments
are nearly coiled around rhesetranscription
arrangement that follows the theory of quasi-equivalence complexes, so
that each segment is set up to run as an
with greater precision than seenin other virus srructures. independent machine
without tangling the enormously
There is no need for conformational switching in this layer long piecesofdsRNA.
since the vp3T2) subcoreacts asa scaffold upon which the
Crystallography ofviruses has come a long way in the last
VP7(T1 J) layer assembles.Intriguingly there is evidence 20 years.Nevertheless,
the strucrural basesof many of the
from low resolution EM structures of other dsRNA
fundamental biological functions are srill unsolved. These
virusesthat the peculiar arrangement of yp3(T2) may be funcrions are often
carried out by large multi-component
conservedeven beyond the family Reoairidae.Itis tempting
protein complexes.Improvements in the molecular biology
to speculatethat this reflects some fundamental involve_ and purification
techniques for thesecomplexes,along with
ment in the unique biology of these viruses. In most developments in
synchrotron radiation, now provide a way
crystallographic analysesof viral capsids there has been to tackle these
difficult problems. rVe expect crystall_
little trace ofvisible strucrure for the genome. This doesnot ography to
be in the vanguard ofstructural approachesto
mean rhat such structure does not exist, merely that the the major functional
problems in microbiology.
O Prolessor David Stuart
and Dr Jonathan Grimes
are atthe Laboratoryof
Molecular Biophysics,
RexRichards Building,
South Parks Road,
Oxford OXl sQU
O Dr Peter Mertens and
Mr Nick Burroughs are at
the lnstitute for Animal
Health, Pirbright
Laboratory,Ash Road,
PirbrightGU24 ONF
Furtherreading
Chiu, \7., Burnett, R.M. &
Garcia, R.L. (editors) ( 1997).
Structura / B i oI ogy afVirus a.
Oxford: Oxford Un iversiry
Press.
Gouet, P. e<others (1999).
The highly ordered double
stranded RNAgenome of
bluetongue virus revealed by
crystallography. C eI / (in p r ess).
Grimes,J.M. & others (1998).
The atomic structure ofthe
bluetongue vifus core. Natare
395,470418.
Harrison, S.C., Skehel,JJ. &
Wiley, D.C. (1996). Virus
strucrure. In F ieI ds ViroI ogy.
Edited byB.N. Fieids,D.M.
Knipe&P. M. Howley. New
York: Lippincott-Raven.
Rux,JJ. & Burnett, R.M.
(1998). Spherical viruses.Cury
OpinStruct B iol 8, 142-149.
ffi$ffiffi#ffi $#s"ffiwroDAYVOL 26l MAY99 E
Nuclearmagnetic resonancg(NM R):
keeping paCewith micrcbiology
Matthews
Stephen
The primary biological application of nuclear
resonance(NMR) is in the structural
I*agnetic
1|,
toNMRterminology
Aguide
WhatisltlMR?
study of small macromolecules in solution.
V
15N)
(eg rH,13C
interact
nuclei
Certain
Although NMR can reveal high-resolution structures,
These
fields
magnetic
$rength
withhigh
it provides information complementary to both X-ray
withradio
byirradiation
canbeprobed
producing
a crystallography and electron microscopy (EM). NMR
c0ntaining
aspectrum
waves
ofindtvidualfacilitates rapid generation of a three-dimensional map,
Ihefrequency
series
oflines
onthe
lines
tsdependent
spectral
delineating the protein fold in a progressivemanner such
ofthe
environment
chemical
to show clear functional
therelative that early data can be used
nuclei.
Also,
corresponding
can implications. NMR can also be used to look at the dynamic
location
ofnuclei
Ihree-dimensional
Overhauser
thenuclear
using
bemeasured
processesinvolved in complex formation and folding. The
(N0E)
tobe main limitation of NMR is the size of the molecule under
enabling
thestructure
effect
deduced
the larger it is the slower it tumbles in
together with the enterohaemorrhagic E, coli OI51 :H7
(EHEC), a cause of acute gastroenteritis, haemorrhagic
colitis and haemolytic uraemic syndrome in humans,
belong to a prevalent family of diarrhoeagenic enteric
bacteria.EPEC and EHEC adheretenaciously to enterocytes
in the gut and induce the formation of classicalsub-cellular
structures known as attaching and effacing lesions.These
E, coli strains produce a protein, known as TIR, which is
transferred from bacterium to host cell, where it servesas a
receptor for bacterial adhesion via the surface protein
intimin. This unique mechanism was only recently reported
and it implies a prominent role for intimin in disease
progression.\7hat is more, a30'I kDa fragment of intimin
(Int2B0) plays a central role in attachment and lesion
the
of
the
efficiency
increases
solution, which in turn
NMR relaxation process.This manifests itself as a severe formation. Despite the clarity of the data presented on
broadening ofthe spectral lines that eventually degradesthe intimin-TIR interactions, severalreproducible studies have
investigation;
eflect
[|vethauser
Nuclear
the
ofmeasuring
way
Anindirect
space
as
through
thatoccurs
interaction
nuclear
between
coupling
theresultof
dipoles
resolution and efficiency of many NMR experiments. As a
consequencean upper limit for molecular size has always
been associatedwith NMR and has therefore precluded its
crystalNMR
Liquid
that
micelles
ofdisk-shaped
Asolution
use in sudies ofvery large complexes.
ofa
alignment
molecular
induces
field
themagnetic
within
macromolerule
ffi Usewith macromolecular complexes
measurable
creates
directly
therefore
and
Recently, the technique has entered a new period of
couplings
dipolar
acceleratedgrowth, which should ensurethat it remains a
0euteration
leading biophysical technique into the next millennium.
(perdeuteration)
orcomplete
The
fractional
The increased use of deuteration together with novel
with
ofmacromolecules
labelling
labelling strategies for proteins and nucleic acids, and
in
ofdeuterons
Sub$itution
deuterons
protons
place
simplificationthe development of transverse relaxation optimized
facilitates
of
spectra
ofNMR
and
improvement
spectroscopy(TROSY) have all extended the applicability
TR(lSY
0ptimized
Relaxation
Transverse
produces
(TR0SY)
NN4R
Spectroscopy
linenanower
withsignificantly
spectra
bythe
experiments
traditional
widths
than
o{tworelaxation
cancellation
mutual
mechanisms,
of NMR to much larger systems; molecular species in
excessof 100 kDa are now tractable. Furthermore, liquid
crystalline media together with the measurement of
residual dipolar couplings enable structural information to
be extracted accurately and easily without recourse to
proton nuclear Overhausereffects(NOEs). NOEs allow the
intimin will adhere directly to mammalian cells in the
absenceofTIR.
ffi lntimin structure
It seemsremarkable that, in the light of the discovery of
intimin about 10 years ago and the recent acceleration
of research into EPEC pathogenesis, the wait for a
detailed structural report has been so long. The very
latest improvements have made proteins of up to 50 kDa
routinely amenable to sttuctural study by NMR and have
accordingly opened the door for an NMR-based assault
on the structure ofInt2B0. The new strategy has proved
particularly successfuland has produced the first structural
HrO+tH
[13C]Glucose
-0o/oD
determination of interatomic distancesthat structures are
traditionally modelled from but these are notoriously
imprecise and often difficult to acquire comprehensively.
NMR can now provide information on the structure of
sizeable molecules and, perhaps more importantly, the
intricate details of large macromolecular complexes are
now attainable in solution. Although NMR does not
compete with X-ray crystallography and EM for tackling
huge structural problems, some major applications have
becomepossible.In addition, NMR still retains its ability
to generate structural data very quickly, which is often
invaluable to the biochemist in the early design of new
mutagenesisexperiments or the searchfor target molecules.
ffiStudies of enteropathogenicEscherichiacoli
This new potential for NMR has recently been illustrated
by the first structural study into the molecular basis of
bacterium-host-cell interactions in enteropathogenic
Escbericbia coli (EPEC) infection. EPEC gives rise to
persistent diarrhoea and is an important causeof mortality
amongst infants in developing countries. These organisms,
E
emerged that suggest a more complex mechanism for
EPEC/host-cell adhesion.These include the finding that
ffiffi$#ffi
#ffi${Ffu#ffiYTODAYVOL26/MAY99
DrO+tH
[13C]Glucose
-860/oD
,,-**tJi/t-nd
Drs+B
ll,,l
llsc]GiucCIse
*g7o/o
s
,
i
iil\ri :i
i'iiill,ir,'li , ,'l,i
il rll'i' "1l'
',1,1
',i ,l
r
I'l
t
' , 1i ' "
i'l i;"
, , , 1 , ,, , , , , , ,1, ' , , , 1 , ,, ,, , , 1 , , ,, , , , 1 ' , ' , , 1 , , ', , , ,
10
8
1 H( P ' P ' t . )
6
l
D2
------->
D3
within full-length intimin and possibly a fourth. The IgSF
domains in intimrn form an extended, articulated Iinker
O P P OPSAI IG
EE
preparation
Fig.1.The
ofthe
proteins
deuterated
anditseffect
onthe
that protrudes away from the bacterium surfaceand confers 1H
N[/R
spectrum
ofInt2B0
a highly accessiblethird domain for adhesion.
T H IPSA G
LEFT
Fig"f. Tertiary
structure
ofInt2B0
and
type lectins, afamily of proteins responsiblefor cell-surface proposed
quaternary
structure
of
carbohydraterecognition that includes animal cell receptors i n t i m i n ,
The topology of the third domain is reminiscent of the C-
and bacterial toxins. Although Int2B0 lacks calcium
co-ordination, the similarity raises rhe possibility of
carbohydrate recognition in the function of intimin and
implies three models for intimin-mediated cell adhesion.
Putativelg domains
Fig. 3 showsthe three plausible models. In model A intimin
binds a carbohydrate moiety that is attached to TIR.
However, the rarity of bacterial glycosylation is inconsistent
with
this paradigm. Model B invokes a bipartite
interaction,in which intrmin interacrswith TIR and a hostcell carbohydrate.Although studies showing that Int2B0
EPECmembrane
glimpses within 6 months of expressingthe protein.
This has allowed the microbiologists concerned to
redirect their researchefforts and make an impact from
a biochemical perspective. Perdeuterated samples were
produced,in which all the alphatic prorons were replaced
by a deuteron and the amides were re-exchanged wirh
protons.The standardNMR isotopesof nitrogen 1t5\) and
carbon (13C) were also incorporated. The removal of the
strong dipolar interaction involving protons drastically
and fragments of Int280 will bind cultured epithelial cells
in the absenceof TIR add confusion to the intimrn-TlR
story, the data do provide circumstanrial evidence to
support this model. Desprte this, we cannot rule out afinal
scenario, model C. Here the C-type lectin similarity is
incrdental and intimin interacts with TIR directly.
The structural similarities of Int280 with animal
intercellular adhesionmolecules are intriguing and provide
remarkable insight into EPEC adhesion. This work is
probably the first demonstrarion of the usefulness of
combined perdeuterarion/site-specific protonation and
increasesthe short relaxation times normally associated NMR spectroscopy strategy. A good molecular understanding ofbacteria-cell interactions is crucial for targeted
resolution and the sensitivity of many of the complex development of rational drugs and will have implications
with a molecule of this size.This improves both the spectral
multidimensional, multiresonance NMR
experiments
that are necessaryto complete a structural assignment.
Uniformly deuterateditN/l3C-labelled material is readily
preparedby growing bacteriacontaining the recombinant
geneof choicein a defined medium that utilizes 11NH4CI,
ll3Clglucose and D2O as isorope sources.If protonared
glucose is used deuteration levels of up to B6 %ocan be
achieved,but to accomplish full deuteration, a deuterated
carbon source is required. Fig. 1 shows the effect of
deuteration on the one-dimensional 1H NMR specrrum
of Int2B0; the narrowing of the line widths and associated
spectralimprovement are clearly visible. Further perdeuteratedsamples,in which residuescontaining methyl groups
arespecificallyprotonated, afforded sufficient NOE distance
restraintsto facilitate the calculation ofa global fold.
F i g . 2 s h o w sa s c h e m a t i cr e p r e s e n t a t i o no f t h e t e r t i a r y
and quaternary structure of intimin. Int280 is highly
asymmetric,approximately 90 A in length and built from
three globular domains. The first two domains each
comprisetwo p-sheetsandwichesthat resemblethe classic
immunoglobulin superfamily (IgSF). Tandem repeats of
IgSFdomainsare ubiquitous within cell-surfaceadhesion
moleculesand are responsible for a variety of molecular
recognitionprocesses.Sequencealignment indicates the
presenceof a third IgSF domain N-terminal to int280
for the design of novel drug delivery systems.
O Dr Stephen Matthews is a lecturer in the
D epartm e nt of B i och e m i stry, I m pe ri al C o II eg e of
Scrence, Technology and Medicine, Exhibition
South Kensington, London, SW7 2AY
TeL017 1 594 5315; Fax017 1 594 5207
e-maiI [email protected]
Road,
T H IPSA G
BE T O W
ili*. *. The
three
structurally
derived
models
forintimin-host
celladhesion
P|]0T0S
C0URTESY
STTPHEN
ftilATTI]tWS
Uthata Ramanspectrum Gantell the
micrcbialecologist
NozomiYtow
Microbial ecologists are mostly interested in the
types of microbes present in communities and
level ofnoise in the system and second,the heterogeneity of
their contributions to ecosystemprocesses.It is,
therefore, desirable to know which are the predominant
ofeach cell is not unique, so that calibration is effectively
impossible. Another widely used optical technique is
species in a community, their abundance and their
metabolic contributions. It is well known that most
microbes in natural communities cannot be cultured in
fluorescencemeasurement,often in combination with laserbased cytometry, which can give information about the
the laboratory, at least with current techniques, and this
severely restricts identification of even predominant
microbes (ordinary bacteria or archaea)becauseidentification classically relies on responsesto specific media and
phenotypic expression under definite cultural conditions.
Oligonucleotide molecular probes can help this situation,
assuming that a microbial sample is available and we know
what we should be looking for. They can also yield information on the abundance of microbes and, with some
sophisticated treatment, can provide estimatesof metabolic
activity; hencetheir power astools in microbial ecology.
Although molecular probing is a powerful and
moderately straightforward technique, it still requires
samplesto be taken from the natural environment. Natural
of molecular probes; if we are not sure what is there, we may
get no information or, even worse, we may get misleading
information. \7e need a method with intermediate
'resolution'
that can tell us which types of molecules, rather
than which
individual
species, are present. Raman
spectroscopyallows us to do this.
The Ramanspectrum
A Raman spectrum is a set of very narrow spectral lines
emitted from object molecules when illuminated by an
incident light. The width of each spectral Iine is strongly
affectedby the spectralwidth ofthe incident light and hence
tightly monochromatic light sources,such as lasers,are
used. The wavelength of each Raman line is expressedas a
wavenumber-shift from the incident light, which is the
The spatial and temporal structures of ecosystemsplay
important roles in their dynamics becausespatio-temporal
difference between the inverse wavelength of the Raman
line and the incident light. The wavenumber-shift, not the
heterogeneities can be driving forces for life processes,for
example a redox gradient in soil is a driving force for the
particular atomic groups in molecules.
microbial soil ecosystem.Periodic material exchange by
can be generalized as spatio-temporal heterogeneities,
especially when these two elements are conjugated in a
single ecosystem. Upwelling in aquatic systems and
hydrothermal vents are qp<amplesof such conjugated
dynamic ecosystems.An understanding of the spatiotemporal effects on natural microbial dynamics requires
continuous observation which cannot be accomplished by
discretely sampling an ecosystem.
There are also casesin which sampling is difficult for
technical feasons,such asin deep-seahydrothermal vents. A
deep-seahydrothermal vent ecosystemcan be summarized
as being driven by nutrient-rich hydrothermal effluent
supplied from small chimney orifices (high temperatute
black smokers) or from narrow cracks ('low' temperature
effluent, referred to asshimmering). These sourcesare small
and sparseand the use of submersibles (manned or unmanned) is essentialfor observation and for taking samples
from these systems. This places severeconstraints on both
the number and amounts of samplesthat can be recovered.
Continuous observation using optical methods is one
solution to the sampling problem. Measurement of turbidity, i.e. light-scattering, is commonly usedto determine
ffiffi"#ffi
amount of fluorophore present. Although it can be used for
continuous measurement, it has a similar restriction to that
communities do not exist inside laboratory flasks but as
components of ecosystemswith spatio-temporal structures.
tidal action is an example of heterogeneity in time. These
spatial gradients and temporal changesin environments
E
microbial communities means that the optical contribution
absolute wavelength, of the Raman lines is specific to
Raman spectrameasurethe vibration statesof molecules
which are determined by their molecular structure,
especiallyby atomic groups such as methylene, ethylene,
amide, phosphate or sulphide. Most applications of Raman
spectroscopy in biology are concerned with change in
states of macromolecules or related small
vibration
molecules. Changes in either the wavenumber-shift of
single Raman lines or the relative intensities of two or
more Raman Iines in an atomic group have been interpreted
as indicating conformational changesin macromolecules.
For these reasonsRaman spectroscopyis mainly used for
qualitative studies of molecules and molecular dynamics
in biology. For easier and clearer interpretation of Raman
spectra, use of the technique has been restricted mainly to
purified materials and their systems, such as enzyme
reactions.However, becauseRaman spectraare basedon the
specific vibrations of atomic groups we can also use them
to charactenze and quantify a mixture of molecules as
compositions of atomic groups by a method akin to fingerprinting. Although unable to resolve the composition of a
sample in terms of a list of chemical compounds, it doesgive
a rough sketch of the molecular composition of the natural
environment and how it changeswith time.
Resonance Ramanscattering
cell density in the laboratory, where it gives good results for
pure cultures. It cannot, however, be applied to natural
The Raman effect is an induced emission of light and
its efficiency (intensity for the same incident intensity)
communities for two fundamental reasons. First, the
presenceof non-living particles createsan unacceptable
depends on the energy interactions between photons
and molecular groups. \When object molecules have
TODAYVOL26/MAY99
ResonanceRaman
chromophores with an absorption wavelbngth nearly
matching the incident light, the efficiency of Raman
scattering is considerably increased.This enhancemenr
phenomenon, known as resonanceRaman scattering, is
different from non-resonanceRaman scattering. Alrhough
they differ in efficiency and application, they share the
sameprinciple of non-elasticlight scattering. Non-elastic
scattering is a process involving energy transfer, hence
the energy of incident and scatered photons is different.
Since the energy of each photon is equivalent to its
wavelength, non-elastic scattering can be detected as
the emission of light with a different wavelength from
the incident light. The energy difference of the emitted
photon reflects the energy level in molecules, which is the
atomic group vibration within molecules in the caseof
Raman scattering. By contrast, for elastic light scattering
it is momentum, not energy,transferred between photon
and molecule, which results in a change in the direction
of the photon, i.e. reflection and refraction. This can be
used to provide information such as the shape of whole
objects as a result of the phase interference between
scatteredphotons.
Resonance Raman scatrering may sound like fluorescence,but it is a completely different process.Fluorescent
light is generated after absorption and re-emission of
Non-resonance Ramanscattering
Similar Raman scattering also occurs even without
resonanceor absorption and is called, not surprisingly,
'non-fesonance
Raman scattering'. By contrast to resonance
Raman scattering, which is only observed in molecules
which resonare with the incident light, non-resonance
Raman scattering occurs with all molecules, excepr in cases
where Raman emission rs prohibited by a physical law, the
'selection
so-called
rule', which relates to the shape of
molecules determining their vibrational modes. This nonspecificity means that non-resonanceRaman specrroscopy
can be used as a general tool to chancterize and to quantify
organic matter in the natural environment. All natural
organic molecules contain either methyl or ethyl groups, so
estimation of the concentration of these groups gives a
measureof the organic carbon concentration. Simultaneous
a photon by the chromophore, but resonance Raman
emission is induced without the absorption of a photon.
recording of Raman bands corresponding to methyl/ethyl,
amide and phosphate groups provides a fingerprint of the
organic molecules present. The generality of non-resonance
They can be practically distinguished; when the wavelength
of incident light is changed within a comparatively
Raman scattering means that it can provide a simultaneous
record of a wide range of molecules.\7hen we find a spectral
wide tolerance fluorescence spectra are not affected. The
wavelength (i.e. absolute wavenumber) of a Raman line, on
pattern indicating the existenceofa molecule of interest, we
the other hand, varies with that of the incident lighr to
keep the Raman shift constant. Also Raman scattering
induced by a laser light gives much narrower spectral lines
compared with
the broad spectrum of fluorescencl;
the former is of the order of spectral band width of the
incident light (commonly less than 1nm with currenr
lasers),but the latter is 10 nm or more and is not affected
by the band width of the incident light. Using these
differenceswe can distinguish, for example, between
carotenoids and chlorophyll in phytoplankton cells in
uiao, without any chemical treatment. Carotenoids can
be detected as spiky Raman lines beside the broader
fluorescencefrom chlorophylls. This is an unexpected
result, considering the relative abundance of chlorophyll
and carotenoidsin phytoplankton cells. Either the energy
ABOVE:
S c h e m adti iacg r acm
o m p a rR
i nagm a n
s c a t t e rw
i ni g
t hf l u o r e s c eEnacceh
b u n dol efh o r i z o nl rt na el i sn d i c a t e s
e n e r gs yt a t eosfa m o l e c uLl ien,ei n
s
e a cbhu n drl e p r e sveinbtr a t ieonne r g y
l e v ecl so r r e s p o nt o
dei nagcehl e c t r o n
e n e r gl eyv eDl ,a s h h
eo
d r i z o nl itnael s
i n d i c avtier t u ea nl e r gl eyv e lUs p
, ward
a r r o wi nsd i c at theea c t i oonfi n c i d e n t
p h o t oannsdd o w n w a r rdo wi nsd i c a t e
e m i s s ioofp
nh o t o n
Tsh,el e n g o
t hfe a c h
a r r ocwo r r e s p ot o
ntdhsee n e r g
o yft h e
p h o t ownh i cihsi n v e r speri yo p o r t i o n a l
t ot h ew a v e l e nogftthhel i g hTt h e
h o r i z o nstpaal c i n
bg
e t w eaernr o w s
indicath
ee
st i m eb e t w euepnw a r d
s ,l e c t r o n
a n dd o w n w p
ar 0
d c e s sAene
i nt h em o l e c ui sleex c i t ebdyt h e
p h o t oi h
ne
:f l u o r e s c e n c e
a b s o r p toi foan
p h o t oi sne m i t t e
ad
f t earr a n d odm
elay,
I nt h ec a soefb o t rhe s o n a a
nn
ce
dn 0 n r e s o r l aR
n caem at h
ne
,u p w aar d
nd
s eusst ta k e
place
d o w n wp
ar 0
dc e s m
s i m u l t a n e of o
u rst hl ya;rte a s oi tni s,
r e f e r rteod
a sat w 0 - p h 0pt 0r 0nc e s s ,
can then apply more specific methods to obtain grearer
detail. This is perhaps the greatest porential that rhe technique has to offer microbial ecology. It also provides the
opportunity for a continuous monitoring method to give
a spatio-temporally continuous view, which is highly
desirable for understandinq the nature of microbial ecosystems.
lncidentlight
Resonance and non-resonance Raman scattering differ
not only in specificity but also in sensitivity. Application of
non-resonance Raman scattering is limited by the far
weaker intensity of scattered light which arisesfrom the
nature of Raman scattering. Unlike absorption, Raman
emission is the result of an interaction between an incident
photon and the molecule, which is a much rarer event. This
transfer between chromophores or the intracellular results in a much lower intensity with rhe same intensity
structurein which thesechromophores exist musr suppress (flux of photons) of incident light. Furthermore, rhe
fluorescencefrom chlorophyll. Indeed the chlorophyll
fingerprint region of organic molecules in Raman spectra
fluorescence of solvent exrracts from phytoplankton
is rather close to the wavelength of the incident light.
cells makes detection of the carotenoid Raman band
difficult. Thus, resonanceRaman spectroscopyenablessuch
'optical'extraction
of molecules. The choice of incident
laser wavelength determines which molecules will be
excited, and hence we can differentiate molecules of
interest.
Conventionally, tandemly aligned double or triple specrrometers have been used as filters to eliminate stray incidenr
Iight. Sensitive detectors and long exposuresare necessary,
not only becauseof the weaknessof Raman emission but
also due to optical losses in tandem aligned multiple
ffi $ffiffiffiffi$sffi ffiYTODAYVOL26/MAY99E
spectrometers. For longer exposures,thermal background
noiseof the detector must be reduced and electrically cooled
charge-coupled device (CCD) detectors are now commonly
used for Raman spectroscopy.Incident light sourcesmust
have very narrow bandwidths becauseRaman lines carry
over the bandwidth of incident light, and a broad spectrum
of incident light reduces the spectral resolution of Raman
spectra.The light sourcealso must have high intensity and
be well focusedto optimize efficiency of the optical systems.
For these reasons,lasersare commonly used as light sources
in modern Raman spectroscoPy.
Fieldapplications
Raman spectroscopy has been largely used in laboratories
with a specific interest in molecular vibration, so highresolution spectrophotometershave normally been used.
Spectrophotometerswith longer optical paths have been
preferred becausethese enable better spectral resolution. A
longer optical path, however, results in greater optical
loss in the system so demands longer exposureand a more
intense light source,which again meansa lasersource.These
problems have made the application of Raman spectroscopy
in field researchdifficult. Smaller optics are preferable for
field use not only for portability but also becausethey are
brighter, enabling shorter exposuretimes (i'e. more data),
and consume less power (the light source and the CCD
cooler are the main power consumers in Raman spectroscopy). Field applications sometimes do not require the
high spectral resolution demanded by the specialist
laboratory and hence we can reduce the size ofthe optical
system by restricting the spectral resolution within an
acceptable range. Nowadays improved optical elements
are commercially available, although some of them are
restricted for military trse, which permit the field
application of Raman spectroscopy.Higher sensitivity
resonance Raman spectroscopy would also expand the
arcaof application by facilitating the detection at lower
concentrations of the object molecules with lower power
incident light and with shorter exposuresto improve the
time resolution of the process.Combination of resonance
Raman spectroscopy and fluorometry would give another
approach to quantifying biological pigments.
Conclusions
Furtherreading
Ferrano,J.R. & Nakamoto,
oryRaman
K. (I99 4). lntroduct
Specnunpy.London:Academic
Press.
Laserna,JJ . (editor) ( 1996).
in Raman
ModanTecbniques
Spearunpy. Chichester:John
\filey&Sons.
Turrel, G. & Cortset,J.
(editors)( 1996).Raman
and
oPments
Microscopy.D euel
Academic
Applicati ons.London:
Press.
E
Raman spectroscopy has emerged from the physics world
and has been applied in specializedbiophysical laboratories
as a technology to investigate molecular dynamics.
Improvements in each component technology are cfeating
an opportunity for wider application, including microbial
ecology. Raman spectroscopyis now gaining the ability to
be usedfor general field observations.
O Dr NozomiYtowis basedin thelnstituteof
Tsukuba,
of Tsukuba,
BiotogicalSciences,University
lbaraki305-8572Japan
ffi TODAYVOL26/MAY99
ffi&ffituffi
ffi&ffiffiffi
Bacterialclassification and taxonomy:
a,primertf,orthe new millennium
Gest
Howard
that a single molecular marker,
165 rRNA sequence,can serve to decipher the
evolutionary phylogeny of bacteriahasapparently
The notion
led to significant effectson the minds of many investigators'
These effects include: (a) a generalamnesia about the long
history of thought and debate on the classification/
taxonomy of bacteria, (b) some confusion about the
distinction between actual bacteria and what can be called
'virtual
computer bacteroids', (c) a mental void on the long,
rich and important history of research into microbial
nutrition, which led to the elucidation of many basic
principles of biology and cell biochemistry, (d) belief in new
'discovery'
of a
myths such as the recently trumpeted
'uncultivable' microbes as
great diversity of free-living,
indicated by molecular biological probes' and (e)
implantation of the misconception that the classification of
bacteria should be largely, if not entirely, based on
How
l}0
evolutionary phylogenY.
The immediate inspiration for this article was a sentence
used by Sydney Brenner (1997) in an imaginary letter sent
ThcChirn-pansg
to a mythical nephew, namely "l can't seetbe woodfor the
'wood',
I have selected
phylogenetictrees".To help see the
W
Tert
ilhe
tsrrrdds
Fnrom
The
Ftowers
,Amd
0tlhen
Woodauts
'Verses
items from the extensive researchliterature that illustrate
the problems encountered in the historical development of
bacterial classification and taxonomy schemes. This
'primer'
is offered as an elementary guide, as we enter the
next century, to the somewhat chaotic status of this
important aspectof microbiology'
Thesituationin 1946asviewedbyG.B.vanNiel
indeed hydrolyse gelatin, but these reincarnations do not
reflect appreciable advancesin an understanding of its
basic features or evolutionary relationships. This example
indicates how confusion is introduced into the research
Iiterature, text books and computer information retrieval' It
is alreadyhappening.
Genusand species
How are bacterial generaand speciesdefined? An authority
on this matter is Bergey'sManual of SystematicBacteriology.
The definitions are, in fact, abit fuzzy, especially that of
genus. From the M anuaL.
Genus: "Tbe bacterialgenasis usually a auell-definedgroapthat
is clearly separatedfromothergenera,and the thorough ducriptions
of generain the 1984 edition of Bergey'sManual exemplify tbe
depth to which tbis taxonomicgroup is usaally known. Howeuer,
thereis sofar no generalagreement0n the definition of a genusin
subjectiuity is inuoluedat the
bacterial taxunnrny,and consid,erable
genusleuel.lndeed, what isperceiuedto bea genusby onepersznmay
by anothersystematist"'
beperceiuedas beingrnerelya species
may berqgardedas a collectionof
Species: " A bacterial species
strains that sharemanyfeaturesin commonand dffir considerably
as tbe type
from otberstrains. ..Onestrain ofa speciais designated
and
strain; this strain seruesas tlte name-bearerstrain of the species
for
is tbepermanentexanple of tbe speciu,i.e. the refaencespecimen
the nam.e.Tbe typestrain bas great importancefor classification at
the speciesleuel, becaasea speciesconsistsoftbe type strain and all
to besfficiently similar to it as to
otberstrains tbat are considered
. ."
In 1946, thegreat microbiologist C'B. van Niel published a warrant inclusionwith it in tbesqecies.
'The
relationsbips
classificationand natural
thoughtful essayon
NumericaltaxonomY
of bacteria'in which he reviewed the history of earlier work
an application ofthe
aimed, in part, at developinga stable and generally accepted In 1953, Sokal and Sneath described
in which as many
taxonomy
to
approach
Adamsonian
nomenclature that would eliminate duplication or multiused and given
are
possible
as
characteristics
diagnostic
plication of names for the same organism' He emphasized
organisms
between
relationship
of
The
degree
weight.
equal
among
relations
phylogenetic
that even if we knew the
of the number of similar
a
function
to
be
was
considered
not
would
relations
such
on
based
classification
bacteia,a
'similarity
coefficient.'
characteristics and is expressedas a
necessarily be the best or most efficient for determinative
has been demonstrated
taxonomy
numerical
of
The
utility
purposes.
in a number of studies. Sneath reviewed the 3O-yearhistory
/{md
n&ustmttons
Wtt\tams
Wood
tsgRohwk
Ghanging namesof bacteria
determinative keys are very important in
practical matters (for example in medical microbiology,
public health microbiology and plant pathology), this tends
to be forgotten by those probing evolutionary relations
using molecular markers. The latter press for revised
Although
taxonomic schemesand this inevitably leadsto proposalsfor
changing namesof bacteria.
Particularly egregious instances of name changing
have afflicted the anoxygenic photosynthetic bacteria
group. Example - The purple photosynthetic bacterium
Rbodocystisgelatinosa isolated in 7907 was renamed
Rbodopseudomlnasgelatinosa in 1944, redesignated
Rbodocyclusgelatinosusin 1984 and in 1991 the name
Rubriuiuax gelatinosuswas proposed. The bacterium does
trI ffi HS*&HISffi&VrcDAYVOL26IMAY99
of numerical taxonomy in 1995 and concluded that
"Numerica/ taxunllny in tbe broad senseis tbe greatestaduancein
systentaticssinceDarwin or perhapsLinnaeus. lt bas stirnulated
seueralneu areas of grotutb, including numerical pbylogenetics,
r i cs and nurrteri caI i dentifi cati on
ruoI ecuI ar t a x 0nyrny,morph ornet
"'
does not assumephylotaxonomy
Even though numerical
genetic relationships, it is obvious that closecorrespondence
of a large number of phenotypic characteristics has
something to sayabout genetic connections.
Cowan'scommentson taxonomy (1970)
" A bitberto undetectedsimilarity existsltetweenLewis Carroll's
Alice and taxonomists, and bacterial taxonomists in
particalar...taxlnlrny can - and does- driue taxonomiststo a
tlpsy-taruy Vonderland. . . " lAuthor's note: this paper was
basedon a seminar Alice inTaxonomylandattheUniversity of
ualidity of adjacent taxa was being questioned.Many generaare
Maryland, 5 May 1969.). . . "lt is surprisinghow rnanyso-called beterogeneous
from tbe molecularuiewpointand tbis would imply
publishedin BergeylManual
that all tbeir speciesrnust bestadied beforedeciding on tbe new
microbiologists
look upontbescbemes
( 1923-1957 ) as if theywerenot only usefalgeneralclassifications disposition of thegenul This still leauesanansweredthe questionof
of bacteria, but onestbat bauereceiueduniuersal approual, botb on
boutbornogeneous
tbespecies
are."
Bergey'sManua/ is not uniuersal,euenoneartb; I am notyet ableto
judge its receptionin beauen.. ."
Cowan pointed out that elaborate rules have been
stipulated in codes of nomenclature in the attempt to
Moreon moleculardata
In 1994, Murray and Schleifer pointed out that the
international nomenclature code " is not able toprouidesensible
regulate the formation and use of names,"but tbesecodes
would
regulation of nomenclaturefor new taxa defined by uery limited
data, suchas a nucleotidesequencefora small portion of thegenome.
deligbt tbe bearts of lawyers because
they are t00detailed and try to
Tbe constructorsof tbe original code(1957) and theJadicial
caterfor all euentualities.ln the euent,they are confusingand self- Commissionconsideringthe 1976 and 1990 reaisionsdid not
confuadicting.. ."
foresee0r act upln tbepossibilitiesfor molecular descriptionand
"Tbe Bacteriological Code {i.e., International Code of typification ofprokaryotesthat werenot yet cultiuable. As a resalt,
Nomenclatureof Bacteria] sbould besinrp/ified by deleting the formal namesare beingproposedfor uncultiuated prokaryotestuhose
It sbould consistof Principles, and uniquenessis defined only by uery lirtited cbaracteristics, suchas
Rulesand Recornntendations,
discretion sbould be giuen to bacteriologists to apply tbem
dffirencesin a molecularsequence.
..
intel/igently." The magnitude of the problem that Cowan
A noael sequence
isolatedfrom nature merely indicates that
tberemay bea unique organismin tbe enaironrnent.Howeuer,one
discussedis indicated by List no. 22 published in the
lnternationa/Journal of SysternaticBacteriology(36, 1985),
which contains 44
new names, new combinations,
synonymsor revived names.
Exampleof a rule from the Code
Wffi
lflheHem, The Llclhrcn.
earth and in beauen.I ant assuredby my nlleagau that approual of
Lrchens,regardless
ofconyenlions,
Ixistin onl!turodirrensions,
fi ti{erestrictedto a plane.
0niochsandstones
a sieenish
slain,
Theuliveuponthesim-pleSt
{.rre.
qf
Adfop deru,
a brealliofair.
ContiaitthernuriththeireeduHen.
ffndherlnostcareless
reeindn.
Sheshuns
thebanenslone!
dndrocks.
'
flndthrives
upontheSarbase
bor.
bas to take into considerationtbat sorrtetirnes
sequencingand/or
amp/ification errlrs simulate a noue/sequence,
suggestingsome
intraspeciesdiuersity, or tbat formations of cbimeric sequences
may
bepossible.Moreouer,tbepossibility tbat tbe sequence
uas retrieued
from cell-fru (naked) DI'{A cannot beexcladed,and it ntay haue
"Rule 56b. A conserued
narne(nontenconseraandum)
is a name originated froxt an organism not originally growing in the
wbicb rnustbeusedinsteadof all earlier synlnllns and homonyms, exarninedbabitat. . ."
'environmental
Note 1. A conserued
narne(nomenconseruandum)is conserued In fact, it was recently demonstrated in an
against a/l otber namesfor the tAxln, whether theseare cited in tbe
ecology' study, that RNA
correspondinglist of rejectednames0r nzt, so long as tbe taxon
indicating the presence of certain bacteria in natural
sequence data supposedly
concerned
is not united with anotber taxon bearing a legitimate
sampleswere due to contaminating 165 rDNA introduced
name.ln tbe euentof union or reunion with anotbertaxon, the
in the exquisitely sensitivepolymerasechain reaction.
earlier of the two competingnarnesis adopted in accordancetuith
Ralu 23a,b."
Concludingremarks
The intent of this rule, to stabilize nomenclature, i3
The assumption that our current knowledge is sufficient to
excellentand is quoted here only to illustrate the quasi-legal
(sometimesconfusing) language of the Code.
waffalt new, presumably'finaI' , names for many genera and
speciesis obviously questionable andarrogant, and evokes
Cowan's admonition: "lt is ofteneasiert0 createa newgenus0r
' Sneath's1989assessmentofthe utilityof
molecular seq uence markers i n classification
andtaxonomy
species
tban to do tbe cornparatiaework necessary
t0pat dn organism
into its rigbtful place in an existing genusor species.
Tbe temptation
to designated.newgenusor species
sbould beresisted."Obviously,
"Amajor dfficulty with curcentlyauailable molecularsequences
is as knowledge advanced, numerous name changes were
thefax tbat theyare only sanrpla of relatiuely small size,Sam.pling proposed and many were reasonableand useful, for example
the change from Streptlclccxtslactis to Lactococcuslactis.
enor will tbereforecontinueto dominatetbepicture. . .
)ne area that is now being explored is the use of molecular
'signatures',that are cbaracteristicofuarious
small sub-sequences
During the past two decades, however, the notion that a
bacterialgroupings.Tbeir ualue will dependconsiderablyon bow
phylogeny has driven a deluge of premature name changes.
clnstant tbesesignaturesa.rewitbin tbe newly defined bacterial
Since recent researchsuggeststhat microbial evolution was
taxa. At presenttberehas beenno detailedanalysis oftbis, tbougb
far more complex than commonly supposed, and probably
some
witbin-taxon aariation is eaident.. .
involved extensive lateral gene transfer, conservatism in
single molecular marker can accurately reveal evolutionary
Anotber morepragmatic questionis bowfar we can safely reuise nomenclature changesseemswell advised.
bacterialclassificationsonpresentsequence
data. ln many of tbe
Carl Linnaeus originated the systematic classification of
earlierpaperson rRNA, strain nuruberswereseldontgiuen, sowe do
plants and animals.ln 17 37 , before microbiology becamea
science,he said "Vhat difficulty basbeencausedto botanistsfrom
notknow whicb weretypestrains. Most tr.,orkers
examinedonly a
singlestrain of a taxon sucb as a genxls,yet tbe analyseswere
displayd as representatiueof the entire taxln - szmetirteswben tbe
tbe reuiual of tbe sciences
down to tbepresentday by tbe inuention of
new.narrtes
is knlwn t0 eaeryonewbo
basbandledthesabject."Alas,
The
c a r t o oonnst h i sp a gaen dt h e
page
opposite
afelakenfuon'How
to
lell theBirdsfrontlteFlowers
and
}therWoodcuts'by
Robert
Willjams
e ru b l i c a t1i o9n5s9 ;
W o o(dD o vP
originally
copyright
byDoddMead
&
C o 19 1 7 ) .
REPRODI]CED
WITH
THE
PIRMISSION
OF
DOVER
PUBLICATIONS
ffi *ffiffiffiffi$#e#ffi ToDAYVOL26/MAY99E
RIGHT;
i'-ii.
w h i lset i lal g r a d usattued e n t
I n1 9 4 9
P r o f e sG
s oersmt a dt eh eu n e x p e c t e d
d i s c o vtehrayat r l o x y g e n i c
p h o t o s y n tbhaect itcefriixam oe c u l a r
n i t r o gH
e nea,n d
h i sc o l l e a ghuaevse
em
d ber
i s o l a taenddc h a r a c t e rainz u
o fn e w
s p e c ioefps u r pal en dg r e e n
c lpuhdstihneg
a n o x y p h o t oitnr o
Rhadospirillum
remarkable
bacterium
was
in
Thelatter isolated
centenum.
g
i
v
e
r
1 9 8a/ n d r h es o eecsn a r ei T
c o m m e m o roaftthi oefna ctth aittw a s
d r s c o v e10
r e0yde a rasf t et rh ef r s t
i s o l a t ioofanp h o t o s y n tbhaect ltceu rm
(Rhodaspirlllun
inpure
culture
grown
When
onagar,
rubrun).
produce
ritlmer0lls
cells
R.centenun
l a t e rfal al gl leaa n dt h es w a r m i n g
(xt hi sef i r s t
p
h
o
t
o
t
a
c o l oense x h i b i t
microbiolo gy today is faced with this old problem.
I ns ) ,
k n o wenx a m pi nlseu cohr g a n i s m
190) observation is timely: "Tbosewbo cannot
Santayana's
t
o
s oersr te f e r s
c o n v e r s aPt iroonf ,e sG
past
w
h
o
to repeatit,"
the
are condemned
o v e r ' z e a bl oaucst e rt iaax o n o m l s t s remextber
w o rd l i k e
t oc h a n tgheen a moefR
There is every reasonto believe that as current genome
r ai ct e s ' ,
c e nnt u
em a s ' t a x o n opm
sequencing projects mature and expand, we will be in a
','.1
Sources
Ends,
Brenner,S.(1997).Loose
p. 57.London:CurrentBiology.
Cowan,S.T.(1970).Heretical
taxonomyfor bacteriologists.
61,145-154.
J GenMicrabiol
Krieg, N.R. & Holt,J.G.
(edit<-rrs
) ( 1984).Bcrgel':
I ogy,
ManuaI afSystemati cBacterio
rVilliams&
Vol.1.Baltimore:
Wilkins.
L a k e . J . A . . J a iR
n ,.& R i v e r a ,
M.C.(1999).Mixandmatchin
28J,
thetreeof life.Science
2027-2028.
(1998).
Murray,R.G.E.
andnomenclature.
Taxonomy
ASM N ews54 (D ec),669-51 0.
much better position to evaluateorganismal relationships
and deal with classificattonltaxonomy schemes more
effectively.In the meantime, readersare referred to a very
useful summary by R.G.E. Murray (1998) of current
problems and procedures in dealing with taxonomy and
nomenclature of bactena.
Attention is also directed to a thoughtful review by
the limitations in using only
Palleroni(1997) that discusses
molecular data for analysisof prokaryote systematics.On
t h e b r i n k o f t h e n e w m i l l e n i u m , t h e s i g n i f i c a n c eo f 1 6 5
rRNA as a ma;'or taxonomic criterion is receding. At the
same time, recognition of lateral (horizontal) gene transfer
as an important element rn prokaryote evolution is gaining
momentum (Lakeetal., 1999).
O Howard Gesf rs Distingjuished Professor Emeritus
at lndiana University, USA, where he works in the
Murray,R.G.E.& Schleifer,
Photosynthetic BacteriaGroup. He may be contacted
K.H. (1994).Taxonomicnotes:
at the Department of Biology, Jordan Hall, lndiana
forrecordingthe
aproposal
U niversity, Bloomi ngton, l N 47405, U SA
properties
ofputativetaxaof
T e l+. 1 8 1 2 8 5 59 6 1 2
IntJ Syst Bacterio
I
procaryotes.
44,]4J16.
e-maiI [email protected]
Palleroni,N.I.Q997).
Prokaryotic
diversityandthe
importance
ofculturing.Antonie
LeeuuenhoekT2,S-19.
Sneath,P.H.A.(1989).
of
Analysisandinterpretation
sequence
datafor bacterial
theviewofa
systematics:
numericaltaxonomist.,lyrl
ApplMicruilt/ 12. I 5-J I.
Sneath,P.H.A.(1995).Thirty
yearsof numericaltaxonomy.
S y sBt i c , l 4 4 , 2 8 I - 2 9 8 .
VanNiel,C.B.(L946).
andnatural
Theclassification
relationships
of bacteria.
ColdSpringHarborSyaQIl,
285-70r.
E
ffiS$#$q#ffiH#$'##tr'TODAYVOL26/MAY99
2ndWorkshop
inMolecular
Biology
1998-9
1999
28December
January
HoChiMinh
City,
Vietnam
ofMedicine
andPharmacy,
University
I Robert
E.Glass
Thistwo week courseconsistedof both practicalsand
, i t h d u a lt r a n s l a t i o n s .
l e c t u r e sl.t w a s d e l i v e r e di n E n g l i s hw
S e v e np e o p l ef r o mt h e U K a n d o n e p e r s o nf r o mT h e
r asDrSimon
N e t h e r l a n d so a r t i c i o a t e dT.h e U K c o - o r d i n a t ow
/- |
, o y a lH o l l o w a y
C u t t i n g( S c h o o l o fB i o l o g i c aSl c i e n c e sR
U n i v e r s i t oy f L o n d o n )a n d D r P h a mH u n g V a ns e r v e da s t h e
Vietnamco-ordinator.
r i o l o g ya n d i t s
T h e c o u r s ea i m e dt o i n t r o d u c em o l e c u l a b
, h i c hi s a d e v e l o p i n g
t e c h n i q u e st o V i e t n a mw
associated
c o u n t r yt h a t c o n t a i n sa s o u n da c a d e m i cin fr a s t r u c t u r e
b y t h e F r e n c h( e . g t. h r e e P a s t e u rI n s t i t u t e s ) .
established
A l t h o u g hV r e t n a mh a sa g o o d b a c k g r o u n di n t h e n a t u r a l
s c i e n c e sa n d i m m u n o l o g yi t, h a s l i t t l eu n d e r s t a n d i n og f
m o l e c u l ab
r i o l o g ya n d h o w t h i sc a n b e a p p l i e dt o r e s e a r c h
a n dd e v e l o o m e n t ,
T h e 4 3 e n r o l l e ds t u d e n t sc a m ef r o m a l lo v e r V i e t n a m( i n r e a l i t y
m a n ym o r ep e o p l ea t t e n d e dt h e l e c t u r e st h a nj u s t t h o s ew h o
w e r e e n r o l l e d )T. h e e n r o l l e ds t u d e n t ss a t a n d p a s s e da n
examset bythe organizersand were awardeda certificate
i n d i c a t i n gt h e i rs u c c e s suf l a t t e n d a n c eo n t h e c o u r s e .E a c h
w a s g i v e na n e x t e n s i v ec o u r s em a n u a lc o n t a i n i n gd e t a i l so f
a l l t h e p r a c t i c acl l a s s e sa n d h a n d o u t sf o r a l lt h e l e c t u r e s .
D u r i n gm y w e e k o n t h e
c o u r s eI g a v es i x 1' 5 h o u r
l e c t u r e so n g e n e e x p r e s s i o n
a n d i t s r e g u l a t i o nI .a l s o
a t t e n d e ds e v e r aol f t h e
practicalclassesand helped
w i t ht h e s ea s w e l la s d e a l i n g
w i t h q u e s t i o n sa r i s i n gf r o m
both the practicalsand
lectures.
of geneexpression
Overview
regulation
DNAtranscription
RNAtranslation
Generegulation
T h e s t u d e n t sw e r e a f a n t a s t i cb u n c ho f o e o o l e I. f o u n dt h e m
r iology.
i n c r e d i b l yk e e nt o u n d e r s t a n da n d l e a r nm o l e c u l a b
O n c et h e i n i t i asl h y n e s so f m e e t i n ga n e w p e r s o nh a dw o r n
off,they were morethan readyto come up and ask questions
a f t e r t h el e c t u r e sa n d d u r r n gt h e p r a c t i c acl l a s s e sI. r e a l l yf e l t
t h a tt h e s t u d e n t sg o t a l o tf r o m o u r p r e s e n c eb, o t h i n t e r m so f
t h e c o n t e n to f t h e c o u r s ea n dt h e c h a n c et o s p e a ks c i e n t iifc
English.
Conclusions
I felt that the coursewas veryworthwhile,lt was clearthat
b o d yo f m o l e c u l a r
t h e s t u d e n t sw e r e l e a r n i n ga c o n s i d e r a b l e
b i o l o g yf r o m u s .T h i sw a s i n d i c a t e db y t h e l e v e lo f t h e
q u e s t i o n sa s t h e c o u r s ep r o g r e s s e da n dt h e i rp e r f o r m a n c e
i n t h e w r i t t e nt e s t ,S i n c et h e s t u d e n t sc a m ef r o m a l lo v e r
V i e t n a mt,h e yw i l lb e a b l et o t a k e t h i s k n o w l e c l ^ oh e n l r n
t epartments.
a n u m b e ro f d i f f e r e n d
O ProfessorRobert E. Glass works in the lnstitute of
Genetics, School of Clinical Laboratory Sciences, QMC,
Clifton Boulevard, Nottingham NG7 2UH
Tel.0115 970 9226; Fax 01 15 970 9906
e-m aiI robe rt.g Iass@nottin g h am.ac.u k
F
International DevelopmentFund reports
Throughitslnternational
Development
Fund,SGM is activein disseminating
information
aboutmicrobiologyto
scientists
in developing
countries,
Hererecent
recipients
of awardsdescribehowSocietysponsorship
h-asbeenusedto advancethe
knowledgeof
microbiologists
in SouthEastAsiaandtosponsorscientistsfrom
other
partsof theworldto attendan international
conference
inthe U K.
3rdInternational
Conference
onAnthrax
7-10
September
1998,
University
ofPlymouth
I Les
Baillie
frk
ffi
W
#fr
ffi
ffi
rLi
f*
af
FS
*4
f#
r*
The conferenceattractedapproximately170 delegates
r e p r e s e n t i na
g l lf o u r c o r n e r so f t h e w o r l dw i t ht h e n o t a b l e
e x c e p t i o no f A n t a r c t i c a ; a p p a r e n tpl ye n g u i n sd o n o t c a t c h
a n t h r a xT, h r o u g ht h e g e n e r o u ss u p p o r to f t h e S o c i e t yf o r
G e n e r aM
l i c r o b i o l o gw
y e w e r e a b l et o s p o n s o rt h e
attendanceof scientistsf rom such diverselocationsas
, u s s i aT, u r k e ya n d C o l u m b i a .
C u b a ,I n d i a R
A l t h o u g hi t w a s a s i n g l es u b j e c tc o n f e r e n c et ,h e
p r e s e n t a t i o nfsi l l e dt h r e ef u l l d a y sa n d w e r e d i v i d e di n t o
s i x m a i nt h e m e s :N a t u r a e
l c o l o g ya n d g l o b a li n c i d e n c e ,
D e t e c t i o nl,d e n t i ifc a t i o na n d c l a s s iifc a t i o nS
, t r u c t u r ea n d
f u n c t i o nM
, oleculab
r i o l o g yP, a t h o g e n e s ias n dv a c c i n e s .
I n a l l3 6 o r a lp a p e r sa n d 5 4 p o s t e r sw e r e p r e s e n t e d .
I n s u p p o r to f t h e s c i e n t iifc p r o g r a m m et h e r ew e r e a
n u m b e ro f s o c i a le v e n t s n, o t a b l va v i s i tt o t h e N a t i o n aM
l arine
A q u a r i u ma, n dt h e c o n f e r e n c ed i n n e ra t w h i c hd e l e g a t e s
w e r ee n c o u r a g e dt o m e e t ,d i s c u s st h e i rw o r k a n d m a k en e w
contactsin spiteof the best efforts of an excellentjazzband,
T h e s ei n f o r m aol p p o r t u n i t i ew
s e r e o f p a r t i c u l avr a l u et o
w o r k e r sn e w t o t h e f i e l dw h o h a dt h e c h a n c et o s p e a kt o
'
o
l
d
m a n yo f t h e
handsi
T h es t a t e da i m so f t h e c o n f e r e n c ew e r e :
O t o b r i n gt o g e t h e rt h e k e y w o r k e r si n t h e f i e l do f a n t h r a x
r p q e a r r - h t n r o r r i o r a rn r n n r A q q t n d e t o
Lv
uuLv,
qnd
sr
rv
O to createa criticalmasswhich will leadto the formationof
n e w n e t w o r k st,h e e x c h a n g eo f i d e a sa n d s t i m u l a t en e w
avenuesof research
I nt h e l i g h to f t h e f e e d b a c kt h a tt h e o r g a n i z e r rse c e i v e d
d u r i n ga n d s i n c et h e c o n f e r e n c ei,t w a s f e l t t h a tt h e s ea i m s
wereachieved.
Forthosewho were unableto attend it may be of interestthat
s e r e r e c o r d e do n v i d e o c, o p i e so f w h i c h
a l l t h ep r e s e n t a t i o nw
w i l lb e m a d ea v a i i a b l eI .n a d d i t i o nt,h e o r g a n i z i n gc o m m i t t e e
i n t e n d st o p u b l i s ht h e p r o c e e d i n g s ,
t
F o rf u r t h e rd e t a i l so f t h e c o n f e r e n c ep l e a s ec o n t a c tm e .
O Dr LesBaillie was the Conference Chairman. He is
basedat DERA, Building 384, CBD Porton Down,
SalisburySP4 0JQ
Tel.019B0
613881
Training
Course
onSRSVVirology
11-24
November
1998,
Beijing
ABOVE:
Participants
ontheSRSV
Virology
Training
Course
heldinBeijing
China
I BinleiLiu
BELOW:
D rB r n lLejiug i v i nagl e c t u r e ,
I n N o v e m b e r19 9 8 l c o n d u c t e da t w o - w e e k t r a i n i n oc o u r s e
i n B e i j i n gC
, h i n aT
. h e c o u r s ew a sj o i n t l yo r g a n i z e dd y t h e
l n s t i t u t eo f N u t r i t i o na n d F o o dH y g i e n eC
, h i n e s eA c a d e m yo f
PreventivM
e e d i c i n eB, e i j i n ga n dt h e D e p a r t m e not f
M o l e c u l aM
r i c r o b i o l o o yU,n i v e r s i toy f S o u t h a m p t o nl t.
i n c l u d e dt h e i n t r o d u c i i b n
o f r e c e n ta d v a n c e si n s t u d i e so n
s m a l lr o u n ds t r u c t u r e dv i r u s e s( S R S V so, r N o r w a l k - l i k e
v i r u s e sa
) n dt h e a p p l i c a t i o o
nf the immunodetection
( E L I S A )t e c h n i q u e sf o r S R S V si n C h i n a .
S R S V sc a u s ea c u t e e
, x p l o s i v ed i a r r h o e aa n d , / o vr o m i t i n g ,
and havea high associatedinfectivity,
givingriseto rapid
secondaryspread.Foodand water are majorsourcesof
SRSVtransmission.S RSVshavea worldwided istrib ution
and outbreaksof acute gastroenteritishavebeen reported
i n m a n yc o u n t r i e sA, l t h o u g hC h i n ah a st h e l a r g e s tp o p u l a t i o n
i n t h e w o r l d ,n o S R S Vo u t b r e a kh a s e v e rb e e nr e p o r t e da n d
i n v e s t i g a t i o nosf S R S Ve p i d e m i o l o gay n ds e r o e p i d e m i o l o g y
h a v en o t b e e nc o n d u c t e dt h e r e .
T h e r ew e r e 14 p a r t i c i p a n t si n, c l u d i n gs t a f f ,M a s t e r sa n d P h D
s t u d e n t ss e l e c t e df r o m t h e I n s t i t u t eo f N u t r i t i o na n d F o o d
H y gi e n e .P r o f e s s oX
r i u m e iL i u ,D i r e c t o ro f t h e l n s t i t u t e ,
d e l i v e r e da n o p e n i n gs p e e c ho n t h e i m p o r t a n c eo f s t u d yo n
S R S V si n C h i n a .I g a v el e c t u r e so n t h e m o l e c u l a b
r i o l o g yo f
S R S Va n d i t sd e t e c t i o nu s i n gR T - P C Ra n d E L I S A .T h e
p a r t i c i p a n tps e r f o r m e dE L I S Ae x p e r i m e n t fso l l o w i n gm y
d e m o n s t r a t i oonf t h e t e c h n i o u e ,
Traditionally,
SRSVdetectionhas beenperformedby electron
microscopy.
However,suchexpensiveequipmentdemandsthe
dedicationof a skilledoperatorand unfortunately
this is not
availablefor routrnediagnosticvirologyin developingcountries
suchas China.ELISAoffersa cheapalternative
technology.
S R S V sa r ei h e m o s tc o m m o ng r o u po f v i r u s e si n v o l v e di n
f o o d - b o r n ec o n t a m i n a t i oTn h e d e v e l o p m e not f E L I S A
t e c hn o l o g yf o r t h e s ev i r u s e si s a t i m e l ya n d i mp o r t a n ts t e p
forwardthat is particularlyrelevantto the interestsof the
I n s t i t u t eo f N u t r i t i o na n d F o o dH y g i e n e .
O Dr Binlei Liu is currently a Career-Track Postdoctoral
Fellow atthe Department of Molecular Microbiology,
Medical School, University of Southampton, SOI 6 6YD
T e l . 0 17 0 3 4 9 4 9 4 1 ; F a x O l 7 0 3 7 7 4 3 16
[email protected]
s.ffi
$trffi#ffi $,#n#ffiefroDAy voL26lMAy99 E
Meetingpteview
gwwffiw
ffiffirew
ffiwwwmwxg
ffiKwffi
BruceWard
of
A preview
thetopicsto be
atthe
discussed
S G MM a i n
How
Symposium
Do Molecules
CrossMicrobial
Membranes?
attheUniversity
'
of Leeds
,7-B
1999
September
Transport is an essential component of our
lives. Yet cells display a dexterity in speed of
into and acrossthe endoplasmic reticulum (ER) membrane
of
peptide on the exoprotein is recognized by the Secsystem.In
molecules carried and specificity of carriers that makes
the traffic problems of the M25 look trivial. A major
many Gram-negative bacteria, Sec-dependenttranslocation
problem in both casesis getting to the right place at the
machinery, which is then responsible for the second
(terminal) transport step across the outer bacterial
conveyance, complexity
of
the variety
right time.
to the ER lumen. The hydrophobic N-terminal signal
servesto present a subset ofproteins to the Type II secretion
membrane. Type II secretion requires some 12-16 proteins.
In eukaryotes, some proteins are destined for particular
organelles (mitochondria, chloroplasts, peroxisomes, Filloux will discuss the composition of the proteins in the
'patch'
Type II secretion system and speculateson how the
lysosomesor the nucleus), some of which have multiple
compartments. Others are retained within the general secretion signals of exoproteins are recognized by the
secretory pathway (endoplasmic reticulum and Golgi),
exported to the plasma membrane or secreted from the
machinery. Proteins can be delivered to the SecYEG
cell. Even for the relatively simple prokaryotic cells, the
problem of delivering molecules to the right place at the
export-dedicated chaperone, SecB, or through their
interaction with a signal recognition particle (SRP). In
right time is not trivial. In a Gram-negative bacterium,
macromolecules may be destined for the inner membrane,
eukaryotesa cytosolic SRP binds the hydrophobic signal
peptides of presecretory proteins as they emerge from the
periplasm, outer membrane or the external medium.
No previous SGM symposium has focused entirely
ribosome and delivers the nascent polypeptides to the
on microbial transport, although individual papers on
transport of small molecules (late 1970s), protein secretion
and colleagueswill discuss the evidence for a bona fide
mechanisms (1989-1991) and, more recently, protein
transport in relation to host infection (1993-1997) have
translocaseeither via chaperones,most notably via the
translocaseat the ER membrane. In their review High
SRP-dependent targeting pathway in E. coli.
By contrast Typ" I and Type III systems involve one-step
mechanisms for protein translocation. Type III systems are
been written for SGM symposia. The wealth of molecular
information on transport systemshasJed to an improved
found inSbigella, Salmonella,certain E, coli strains, Yersinia
of the shared features of transporg in
prokaryotic and eukaryotic cells and the complexity of
machinery required to ensure the safedelivery of molecules
Erwinia spp. These systems comprise a sizeable set of
understanding
to the correct location in an active state. Some of the many
current interests in microbial transport are: the nature
of transmembrane channels and the regulation of their
gating; the structure and mechanisms of protective
chaperone proteins; and the mechanisms for ensuring
correct targeting, modulating protein-protein interactions
and plant-pathogenic
Pseudomonas,Xanthomonas and
proteins capableof delivering a number of virulence factors
into mammalian or plant host cells. Schneewind will review
secretion machinery of the pathogenic
the Type III
yersiniae.Some of their proteins are directly injected into
the cytoplasm ofthe eukaryotic host cell (so have to cross
three membranes), whereas others are secreted into the
surrounding medium, or remain bound to the surfaceof
the bacterium. At least three of them require dedicated
and controlling ligand sp".ifi.ity. Hence a symposium on chaperonesfor successfultargeting. Type I systems utilize
transport of molecules acrossbiological membranes seems a periplasmic ABC transporter (ATP-binding cassette)
timely.
of which the cr-haemolysin of E. coli is the best known
example. Typ" I systemsgenerally secreteonly one or a few
Prokaryotic protei n secretion
Bacterial membranes provide essentialbarriers between the
inside of the cell and the external medium. Yet protein
secretion is essential for secretion ofvirulence factors and
extracellular enzymes, and also for the assembly of cell
recognized as substratesby
the ABC protein exporter,
largely by virtue
of the
secondary structure of their
appendageslike pili and flagella. Other proteins have to be
integrated into the inner and outer membranes or exported
C-termini. The dynamics
to the periplasm. Gram-negative bacteria have evolved
a number of systems for coping with the problem of
traversing two rather different lipid membranes (the inner
relatively simple machinery
of the assembly of this
and ofthe Type I secretion
p r o c e s sa r e n o w b e g i n n i n g
proton-impermeable membrane is composed primarily of
phospholipid and proteins while the outer membrane
to be understood. Bacterial
contains lipopolysaccharide as a major component but
relatively few proteins and has channels,called porins, that
systems with
facilitate entry or exit of small molecules). The SecYEG
translocaseof Escherichiacoli plays avital role in transporting
of other transport systems,
proteins into and acrossthe inner membrane. Its eukaryotic
counterpart is the Sec61 complex for protein translocation
E
exoproteins, and these are
3}*S&$mS**$SYTODAYVOL26/MAY99
diversity is shown in Type II
alternative
second steps and in the use
e.g. Type IV systems for
export
of
T-DNA
by
Agrobacteriun'ttilnxefaciens.
-tu
G
?e'l<rs
Euka ryotic protei n tra nsport
dependent translocation acrossthe thylakoid membrane.
Proteins, which are destined for secretion, are firstly
These pathways all reflect the prokaryotic origins of
delivered to and transported across the ER membrane,
chloroplasts. Preproteins destined for the ApH-dependent
then transported to the Golgi apparatus and thence to
secretoryvesicles.These vesiclesmove to and fuse with the
pathway have N-terminal signal peptides that differ subtly
from classicalsignal peptides by the inclusion of a twin-
plasma membrane from whence they are secreted.This
arginine motif bordering the hydrophobic region. The
processhas to be tightly regulated all the way to control inter
Sec- and ApH-dependent pathways seem to be mutually
alia protein conformation and, in the caseof hydrolytic
exclusive and, remarkably, the latter pathway acts on fully
folded precursors. The discovery of the second ApH-
enzymes,prematufe activation. Preproteins can either be
co-translationally targeted to the ER membrane by SRP,
or post-translationally by the Sec63-dependentroute. In
dependent pathway has led to the recognition of the same
type of pathway in bacteria for the export of folded
both casesthe preprotein crossesthe ER membrane via
periplasmic proteins requinng cofactors.A fourth pathway,
a transmembrane channel, which in both yeast and
that may also have a bacterial counterpart, appears to
mammalian cells is composedprimarily of three proteins
(the Sec61 complex). The Sec61p of yeast shows homology
thylakoid membrane.
to the SecY component of the E. co/i SecYEG translocase.
Recent work has revealedthat the transmembrane channel
is much wider than that required to accommodate alinearly
extruded polypeptide, and thus to the realization that
substantial folding of the protein may occur whilst it is still
involve the spontaneous insertion of proteins into the
Protein transport from the cytosol to peroxisomes is
conceptually simpler than chloroplast transport as there is
only a single membrane to cross.\Whilst the vast majority of
peroxisomal proteins are post-translationally imported
from the cytosol (by virtue of short C-terminal targeting
being translocated acrossthe membrane. This and other
signals), it is becoming increasingly clear that peroxisomal
recent advances,such as the revelation that g ting ofthe
lipids and some important peroxisomal membrane proteins
translocase may be accomplished by transduction of
derive from the ER. In her contribution Baker will focus on
conformational changes, that occur in the ribosome as
the biogenesisofperoxisomes.
it translates,will be discussedby Stirling.
\Thilst a branch of this general secretorypathway is used
I nf lux a nd eff lux systemsfor sma ll molecules
for the delivery of proteins into lysosomes,most proteins
For uptake of nutrients the problems are slightly different.
of the mitochondria, peroxisomes, chloroplasts and the
Often the maior one is that the concentration of a metabolite
nucleus arrive at their destination as the result of post-
outside the cell is much lower than that in the cell and
translational import
uptake has to be against a concentration gradient. One
solution is to convert the transported solute into a modified
from
the cytoplasm. Proteins
transported from the plant cytosol to the thylakoid lumen
of chloroplasts have to traverse three membranes: the
outer and inner chloroplast envelope membranes and
the thylakoid membrane. Chloroplast protein transport
is more complicated than origrnally envisaged. Oncd
proteins containing chloroplast transit sequenceshave
been imported
into
the stroma they may undergo
SRP-dependent targeting and Sec-dependent or ApH-
form as in the phosphorylation ofsugars by the phosphotransferasesystem (PTS). Regulation of sugar rransport at
the protein level involves inducer exclusion for Gramnegative bacteria but inducer expulsion in Gram-positive
bacteria. Primary and secondary transport systems for
solutes respectively use energy from ATP hydrolysis and
from ion gradients; they can catalyseboth uptake and efflux.
Poolman will review thesesystemswith particular emphasis
on transport systemsused in adaptation to osmotic srresses.
Efflux systemsare used to pump out antibiotics, heavy
metals and toxic metabolites (including wasre producrs
from intermediary metabolism) from cells and thus help
IEE-L,rmEN-\
I rH's wA'Y /
,/
QoLqt
Tdr5
@A'l
regulate the environment within the cell. Rosen will
I
describethe ubiquitous arsenite efflux pumps and the ways
in which accessory factors improve the efficacy of the
a
Er
resistancemechanism. Specific binding of a peripheral
membrane ATPase to bacterial pmf-dependent arsenite
c a r r i e r sc o n v e r t t h e m i n t o p r i m a r y a r s e n i t ep u m p s , a n d
possessionofan arsenatereductaseeffectively extends the
range ofsubstrates that arsenitetransporrerscan extrude.
Lewis will describe the multidrug resistancepumps
(MDRs) that occur in bacterial,animal and plant cells. By
contrast with solute influx transporters, MDRs have
'n
I
To BE
HE1NT
SIRE qHA'T t wt+s
sEEtns so uNcERmtN
UFE) nf DsTlNfrTloN
Ncf
remarkably broad substratespecificity; amphipathic cations
are generally the preferred substrates,even though MDRs
*ffi$ffi€ktr$$#tu#ffiyroE,ANoL26/N/Ay99
ffi ffi
E
tzr;"i:;:*;"?*r-i
knq.kere'J
ProL€jns
occupy four different mem-
ffi
F,*7#y
--n"3&'te's
J*->
Recurrentthemes
brane protein superfamilies.
Cells use different signal peptides as sorting codes for
A variety of mechanisms
delivery via different systems.Bacterial, chloroplast and
and pathways for the ligand
are used; these include a
yeast pfoteins using the Sec-dependent route have the
'classical'
signal peptide, whereassignal peptides for the
pathway whereby the ligand
ApH-dependent route in chloroplasts and bacteria contain
is flipped from the inner
twin-Arg regions next to the hydrophobic core. These two
leaflet to the outer leaflet of
systems appear to have evolved to transport unfolded and
the membrane and another
folded proteins, respectively.In some casesbipartite signal
where transport is from the
sequencesare used, each to cross one of two successive
outer leaflet to the external
membranes. The old concept of proteins always being
medium using a porin to
translocated in the unfolded state is obviously not true.
tfavefse the outer mem-
Sequence comparisons have proven useful in identifying
brane. The polarity of the
motifs characteristicof particular proteins, e.g. MDR efflux
ligand and its partitioning
translocases can be identified by sequence analysis.
in the lipid
bilayer may
Chaperones are important in controlling the folding and
determine the route of efflux. Lewis will also discussthe
unfolding of proteins. Proteins like SecB and Bip bind
possibility that naturally occurring plant alkaloids would
unfolded proteins to prevent unwanted hydrophobic
Pdg P.pUae t-o-kes
be potent antimicrobials if not for the evolution of MDRs.
interactions. Some chaperones,as in the Yop system, are
As overexpressionof MDRs causesclinically significant
specific to particular proteins to ensure delivery in good
multidrug resistance,the possibility of combating this
shape. You'll neuerwalk alone corld well be the theme tune of
resistanceby using the natural MDR inhibitors produced
by plants (alongside the alkaloids) in combination with
the transport world.
antimicrobials will alsobe discussed.
Sequence comparison studies have been applied to
transport proteins and are particularly
valuable when
applied to membrane proteins, since so little
Space regrettably precludes further discussion of
recurrent themes or of the many applications like antibiotic
resistance,inherited disease,inhibitor design, etc., that
stem from the fundamental science.
hfgh-
However, the organizers of the Symposium onHow Do
resolution structural data exist. Such studies have prbved
MoleculesCrossMicrobial Membranes?hope that this preview
useful in grouping proteins into evolutionaiily related. of the programme is sufficient to whet your appetire ro
families, identifying conserved motifs are of functional attend the sessionat Leedsin September.
significance, etc. Proteins with
six transmembrane
Seeyou there and may you arrive safely!
segments are found in many transpoft families and seem '
to have evolved independently in several families; the
preferencefor this configuration is still unknown. Saierwill
discuss repeat elements withln pefmeases,the recognition
'permeases
with
of fused domains and variations in
O Dr BruceWardhelpedto organizethissymposium
and canbe contactedat lnstitutefor Celland
MolecularBiology,Universityof Edinburgh
TeLol 31 650 5370;e'[email protected]
multidomains.
Roleof lipids
Lipids play crucial and often undervalued roles in transport
of molecules acrossmembranes. The phospholipid bilayer
stabilizes the hydrophobic membrane-spanning cr-helices
from which most membrane proteins are constructed.
Phospholipids may interact directly with the hydrophobic
signal peptides ofpresecretory proteins. The internal and
external layers of membrane bilayers may be asymmetric in
their lipid composition and this may play a role in the
Othersymposium organizers
O Professo
r S. Baumberg
DepartmentofBiology,Universityof Leeds
O ProfessorC.J.Stirling
Schoolof BiologicalSciences,Universityof
Manchester
O DrJ.K.Broome-Smith
Schoolof BiologicalSciences,Universityof Sussex
O Dr P.M.Goodwin
TheWellcome Trust,London
recognition of sequencesresponsiblefor correct orientation
of integral membrane proteins in membranes. For at least
one MDR the membrane influences the substratespecificity
F urtber details of the meetingappearonp, 84 and a bookingform
is onp. 101 . Tbesymposiuru
will bepablishedasa book.A reuiew
of the MDR, by selection only of ligands that partition
and orderformwill appearin afature issueof Microbiology Today,
in the membrane. For example the mammalian Pglycoprotein works by a flippase mechanism (transporting
molecules from the inner to the outer leaflet of the
membrane by flipping them over). Lipids also play vital
roles in vesicular transport ofproteins between organelles.
tril nffi&ffiffie#ffimrroDAYvol26/MAY99
!a:::...
;'1.,:.:i
l:ri,:.ll
Let'shavea debate!
,,:al'],
';:.i:.'r.
r:::,1::.
::r-Ifi
,,11.:lr
ai:.i: rj
.i..:,l
lr,iti
Philip
Mortimer
:,,llri
''ii
rll.:i.
:,it.lt.':
r',.t:
':tt:: tli
I
To be successful,a scientific meeting must provide
a mix of data and interpretation that instructs and
\
stimulates the audience,and leadsthem to modify
their opinions and possibly adapt their research.Sadly,meetings often fail by thesecriteria. Instead, keynote speakersjet
i n t o t h e v e n u e , b e a r i n g s l i d e s .T h e y d e l i v e r a w e l l - h o n e d
speechto a passiveaudience and they leave the same day.
Other speakers(who may at least have paid their way) grve
talks ofvariable quality. A cargo ofoffered papersand posters
is added to the freight ofscientific data, and the audience
begins to reel under the weight of information. Coping
strategiesare adopted, such as lingering in the coffeebar,
getting out of bed late or leaving the meetin g early.The next
time, faced with the prospect of another conferenceof the
samesort, people consult their bulging diaries and decide
that they would prefer instead to ha.vethe information
filtered through the refereeingprocessofthe journals. In
particular, vetefans who might have the most to contribute
to a meeting and are best placed to discussor challenge from
the floor are the most likely not to find rhe time to artend.
Is it then still possibleto organizea meeting thar, rather
that scienceis about facts and not about opinions, but this is
,r
unconvincing. Ideas,not facts,arewhat counr. Ifit is agreed , , , .
that scientific meetings need less undigested fact un4 :.-1-,,
unchallengedassertion,and more discussionand argument, i:,1.,1
:r
t h e n a d e b a r ei s t h e w a y t o b r e a k r h e m o u l d . J u s r a s n o
scientificdata should be taken on rrust until it hasbeen ,-,'.
replicated elsewhere,no scientific proposition should be ,r -,,,
accepteduntil it has been aired in public. If a proposition ,1,,,,.
cannot be defendedin debate there is probably something :,.r.
,,
it. Moreover (and this is an important 1.,-,1
c o n s i d e r a t i o n ) ,p r a c t i c e i n d e b a t i n g w i l l h e l p s c i e n t i s t s , , . '
wrong with
when, in committees or elsewhere,they are called upon to ,,, ..,
present and explain technical issues,and argue for funds.
,i,.:,.,
The subject and the wording of the morion areessentialro ,', :
the successof a debate. It is said that the defeatof the motion ...,,,,,
that'Tbis Hausetuouldfigbt for King and Crtrrntry', at rhe
d e b a t i n g s o c i e t yo f a n a n c i e n t E n g l i s h u n i v e r s i t y i n 1 9 3 3 . , ; , , . , ,
fed Adolf Hitler's ambitions and altered rhe course of ,.,:'.,..,
history. It will take more than the ourcome of a debate -_,,.to change the course of science,yet adebate can bring a :..,,.,.,,,..:
action between old and yollng, experienced and naive,
somnolent post-prandial sessionto life. It can rurn rhe final ,,.,, r,
hours of a meeting from a dispiriting successionof exits by ..:.1:,,
an audiencethat hasbeenfurtively consulting timetables66 i.,'.,,,,
knowledgeable and ignorant? One ploy, which the SGM
identify the earlier train, to an arresting clash of argu-e.rts ..4,'.-l
Clinical Virology Group has been trying out with some
that holds the attention ofall.
than being a failed data transplant, is a successfulinter-
success,
is to include a debatein the programme. A topical
issueis chosenand four or more main speakersare invited to
argue a point. This gets people, both seniors and young
turks, on to their feet to set olrt and defend their opinions
1i.,-,,
Nor should the impact on informed opinion of a well ,.:.,1.
fought debate on a topical issue be discounted. The most ...,..
famous British scientific debate that ever took place was ,..,.,,,.':,
that betweenBishop Wilberforce (known on accountof his
aboutsignificant issues.At the recentmeeting ofthe Society oleaginousmanner as SoapySam) and Thomas Huxley. The '..,,.,.
at -J7arwick,we debated universal screening of antenatal issuewas the descentof man and the outcome was that man's ';'.,.,1,,
patients for HIV infection. The proceedings lasted over rwo relationship to the apescame to be accepted.That o..uslsn ,.,,-.,
hoursand virtually no-one left the lecture theatre.
\Where the form of disputation known as 'the debate'
has not been forgotten after over 100 years,so it should not ....r,1
.
be thought that a debatein a current scientific meeting will ,:,.:..1'
originates is unclear, but it is a structured contest in whidh
countfor norhing.
Attendance at scientific societies,and the SGM is no i.,.,,.r
exception, is suffering from rhe pressuresthat adminis- ..:.,',t.,.
for one side or the other. They do so on the merits of the case trative responsibilities,greateraccountability and growing,.,.'1,:..
opposing views about important issues are set out and
testedin front of a non-partisan audience which then votes
aspresentedby the main speakers.The speakersmay well
seeboth sides of an argument, and indeed might have been
f,
;i
\
teaching commitments put on people'stime. Yet societies .:,.,r1,,'
need members' attendance and their participation u, -..,, t.,.,'''..
ableto argue the opposite one, but their role is to advocate ings just as much as they need their subscriptions. n6sl6s6 :....1-,;11
onecauseand refute the orher. The analogy with English such fellowship a society,however rich ir may be, is mori- :,..,.,r,r
andAmerican coluts oflaw is obvious.
bund. The debate is an occasionwhere seriousissuescan be .,,,..r.;,
The exerciseis academic- no-one is bound by the out- thrashed out openly, and in a form where no*one t, t.r*o- l l:'i.
comeof the motion or by the arguments advanced.A debate,
like a cricket or football match, is simply a game played to
rulesbut it hasa seriouspurpose. It airs and testsargumenrs,
it encouragesspeakers and listeners to evaluate their
cably committed, or immune by virtue of rheir position '..11.r;1.'
from challenge. It is a place where tenured scientists 62n gs .:.il.ir.,i
called upon to defend their work and opinions, and where . -.....,.
the young and lesssecurecan promore theirs.
-,,-,.1.
o p i n i o n sa n d , b e c a u s et h e r e i s a t i m e c o n s t r a i n t , i t f o r c e s
A final warning to the organizersof scientific gatherings:
peopleto structure, prioritize and refine rheir arguments. It a debatecouldserious/yenliuenyour nteeting!
oftenrevealsthe weaknessesof a generally held opinion or
O Dr Philip Mortimer is Convener of theSG M
Debating,an important sedentarysport in British schools ClinicalVirology Group. He can be contacted at
andr"rniversities
until more visceral recreationstook over, PHLS Hepatitis and RetrovirusLaboratory,CPHL,
haslong been in decline, and may be unfamiliar to younger 61 Colindale Avenue, London NWg sHT
scientists.If so,it is time to revive it. It hasoften been argued Tel.0181200 44OO;Fax 0181 2OO1569
themeritsof a minority one.Above all, it is rarelydull.
:,,,,1,:
..,r.....'...
. . : . i . ., . . . , . .
.,r,,l.,:'
t,.t,,,.,,
-.,t,r,:.,
,,,.:.-l
l-
I
ffiwwwwmsffi
ffiryffirasffiffiW
ffiww€#wffi
Microbiology Today
to allconcerned,
O Councilplacedon recorditscongratulations
Janet H urst,lanAthertonandJaniceMeekings,the
especially
team at MarlboroughHouse,on the excellent
production
contentand impactof the f irst issueof
appearance,
MicrobiologyToday.
fbrms of office
OThe Presidentoutlinedsomeconcernshe hadregardingthe
lengthytermsof officeof seniorOfficersof the Societywhich
werepossiblya seriousdeterrenttoablecandidateswho might
takeon theseimportantposts.Councilmaydecideto bringa
resolutionto the nextAG M covering this issue,andcomments
fromordinarymembersof the Societywouldbe welcome.
Gontasts
sometimesarisein fillingnot onlyOfficer
O Difficulties
but alsoon occasionthoseof ordinarymembership
vacancies,
of Council,and in attractinghighqualitycandidatesforthe
ips,Membersagreedthata valuable
Society'sprizelecturesh
toolfor trawlingdepartmentswouldbe a comprehensive,
up-to-datelistof seniorcontactpersonsin relevant
Anyone
institutesand industry.
departmentsin universities,
who couldfulfilsucha roleln theirdepartmentis askedto
contactJanetHurstat SGM Headquarlers.
lnvestment policy
isvitaltothe
OThe efficienthandlingof itscapitalinvestments
futurefinancialsecurityof the Society.Dueto changesinthe
our investment
of DresdnerRCM GlobalInvestors,
organization
FinanceManager
Councilinstructedthe Treasurer,
managers,
andExecutiveSecretarytomakeathoroughreviewof
With
investmentpolicyandthe optionsfor f und management.
guidancefrom our auditorsand afterextensivediscussionby
committee,Councilagreedto transferthe
theTreasurer's
porlfolioto MercuryAssetManagementfor tnvestmentin large,
intheirlastyear
lronically,
commonmanagedf undsfor charities,
managingthe Society'sindependentfund,the Dresdnerteam
haveperformedverywellon our behalfandthe Society'sassets
haveincreasedsignificantlyin notionalvalue.
Public understanding of science
OWiththe appointmentof our EducationOfficer,a number
arecomingforwardand Councilwaspleased
of new initiatives
to approvea proposaltoextendthe useof the Society's
inTeachingFundto includeaspectsof public
Developments
of science,Fordetailsof proceduresfor
understanding
forfundssee p.B 1,
aoplication
Small prizes in universitY
departments
a proposaltof und
O Councilalsosupportedenthusiastically
with
departmentsfor undergraduates
smallprizesin university
Detailswillbe
highlevelsof attainmentin microbiology.
announcedin afuture issueof MicrobiologyToday'
& Charles Penn, General SecretarY
|ODAYVOL26/MAY99
Eil ffi Xffiffi#ffi*#fu#ffiY
ffiw&ffiwffiffi
ffiwwffiffiWWwrefuwww
Annual General
Meeting 1999
OThe Societynoteswith regrettheuntimelydeathof
Professor Gordon 5.A.B. Stewart, U niversity of
Nottingham.ProfessorStewarthad a distinguishedresearch
careerandwas the Society's1997 ColworthPrizeLecturer.
The recentsymposiumvolume(no.5Z MicrobialSignallingand
to which he contributed,has beendedicated
Communication),
to ProfessorStewart'smemory.
TheAnnualGeneralMeeting
of the Societywillbe heldon
Tuesday,7 September 1999,
atthe SocietyMeetingatthe
of Leeds.Agenda
University
papers,includingreports
from OfficersandGroup
andthe Accounts
Conveners,
of the Societyfor 1998 will
be circulatedwiththe August
issue of Microbiology Today.
SGMSymposium
Volumes
tothe
Thecontrrbutions
on
April1999symposium
Microbial SignalIingand
Communicationareavailable
A
57 intheseries,
asVolume
on
review
ofthebookappears
p.66.As
isa60 %
usual,there
buying
members
discountto
The
copies,
theirpersonal
areasfollows:
orices
Memberc
s26,00/$46,00
Non.members
s65.00/$115.00
StudentMembers
s16,00
by
Thebookcanbeordered
postusingtheforminthis
ogyToday.
rssueof Microbiol
Thisformcanalsobeusedto
inprint
orderanypastvolumes
atthetimeof
thatyoumissed
publication,
wishing
Members
Student
Symposium
to purchase
atthediscounted
Volumes
writetotheGrants
rateshould
House
OfficeatMarlborough
orderform,
fora soecral
Wanted
University
GilDomingue,
istryingto finda
of Exeter,
FixedHead10 x 100ml
centrifugeheadsuitable
foranMSEAutomatic
50.lfyou
Superspeed
canhelp,pleasecontact
at
Jorgensen
GilorFrieda
ThePHLSFMRU,Church
Lane,ExeterEX2sAD
(Tel.01
392 402955;Fax
01392412835;e-mail
k)
g,[email protected]
OThe Societyalsonoieswith regretthedeathof
Professor P. Novotny (mem ber s ince 1974), An o b ituary
can be found on the web at http://wvrrwbc.ic.ac.uk/research/
fairweather/obit-novotny.html
Grants
of projects
ffi#ax**'&$epwxw(b)h iExamples
c hm i g h tb e f u n d e d
ffiww*$m,p*"wmmt
i n c l u d et h e p r o v i s i oonf
*
,
"'"
""
't
o
teachingmaterials(e.g.
v i d e o ss, l i d e sp, o s t e r s )t h
,e
d e v e l o p m e notf r e l i a b l e ,
novelpracticalexercises,
new approachesto teaching/
l e a r n i n gf a m i l i acr o n c e p t s
( e . gc. o m p u t e sr im u l a t i o n s
or tutorials)or any other
appropriateaspect,lt is not
i n t e n d e dt h a tt h e F u n d
s h o u l ds u b s i d r zneo r m a l
departmentalteaching
practices;the Societywishes
to encourageinnovation.
u n d e r s t a n d i nogf
m i c r o b i o l o gTyh. e s em i g h t
i n c l u d et a l k s w
, orkshops,
d emonstrations,
posters,
leaflets,broadcasts,
activities
at sciencefestivalsand
audio-visua
o lr c o m p u t e r basedpackages.These
activitiescan take placeas
n a r i o { aS F T e v e n t a t t h e
applicant'splaceof work but
PUS activitiesthat are partof
theprogramme
of anopen
dayto promoteihe institution
a r ei n e l i g i b lfeo r f u n d i n g .
pl...iiti:ti l;',:rr.1lr
.JiL
i:*r: ;:l 1i
Applicationformsare
availablef romthe Grants
Office at SG M HO or may
b e d o w n l o a d e fdr o mt h e
web site,
Yt'r*r.t$*$m'*r*mm$p,m
ffiqlF{$$s:
$r*,,*m#
M e m b e r sw h o a r e
p e r m a n e n t lrye s i d e nitn a
Awardsfor PUS
d e v e l o p i ncgo u n t r ya r e
proiects now available
t h a t t h e ym a ya p p l y
Pleasestateclearlywhethera r e m i n d e d
f o r f u n d i n gt o a c q u i r ef o r t h e i r
Onlyasmallnumber
f o r mi s r e q u i r e d
forateaching
l i b r a r i ebs o o k so, r p o s s i b l y
of applications
to the
aidor a PUS award.
j o u r n a l sr,e l a t i n g
to
Developmentsin Teaching
The nlncinn
Aalalar
microbiology.
Theseannual
Fundhavebeen receivedin
applications
is29 October
awardsare available
as a
recentyears.Thisis probably
19 9 9 .
r e s u l to f a g e n e r o u sd o n a t i o n
d u et o t h e c h a n g i n gn a t u r eo f
f rom Professorl Watanabe
m i c r o b i o l o gt ye a c h i n ga t a l l
o f J a p a n .F u l l d e t a i losf t h e
levelsand constraintssuch
( b )A p p l i c a n t sm u s tp r o v i d ea
s c h e m ew e r ep u b l i s h e o
dn
a st h e d i m i n i s h i ntgi m et h a t
d e t a i l e dd e s c r i p t i oonf t h e
p . 2 4 o f t h e F e b r u a r iys s u eo f
academicstaff haveto
S*$*tS'$'r,ig"
(c) Successfulapplicants
proposedinitiative,
which
it
is
M icrobi ology Today.fhe
d e v i s en o v e a
l pplications.
w i l lb e n o t i f i e di n F e b r u a r y t o a n t i c i p a t ew
d i l l t a k ep l a c ei n
':^
c l o s i n gd a t ef o r t h e r e c e i p t
I nr e c o g n i t i oonf t h i s
"!",
facilitateforwardplanningfor
2 0 0 0 ,f u l lc o s t i n g sa n d
r- r- .. ^. r .--.:..-:
o f a p p l i c a t i o nw
s ,h i c hs h o u l d
" .
situationand in furtherance
:
theirproject.
Theywillnormally evidenceof anycollaborations
be madeto the GrantsOffice
of Societypolicytopromote
berequired
t o m a k et h e
o r o t h e rs p o n s o r s h i pE.a c h
at SG M Headquarters,
is
t h e p u b l i cu n d e r s t a n d i nogf
1999Awads
r e s u l t so f t h e i rw o r ka v a i l a b l e application
shouldalsoinclude
4 O c t o b e r1 9 9 9 .
m i c r o b i o l o g i cias ls u e s ,
O n l yf o u ra p p l i c a t i o nwse r e
t o S o c i e t ym e m b e r sw, i t h i n
a safetyriskassessmentand
C o u n c ihl a sd e c i d e dt h a t t h e
receivedandthe Award Panel
1 Bm o n t h so f t h e a w a r db e i n g evidenceof,or costingfor,
r e m i to f t h e f u n ds h o u l db e
agreedthatthe followingtwo
m a d eT
. h i sw i l li n c l u d ea
a p p r o p r i a tpeu b l i cl i a b i l i t y
c h a n g e dF. r o mn o wo n
presentationat a Society
insurancecoverif the activity p r o j e c t s h o u l db e f u n d e d :
m e m b e r sw i l lb e a b l et o a p p l y
meetingand publicationof an i st o b e h e l da t a p u b l i cv e n u e . r{lr i;i, '.f;.ri!i,
CAL Unit,School
for smallg rantsfor relevant
article in Microbiology Today. Paymentsto helperssuchas
of Health,Universityof Wales
sciencepromotioninitiatrves
Physicalmaterials,
whether
undergraduates
who are
Swansea:to developa case, .^ . . . . . )
a sw e l la s f o r f u n d i n gt o
o f fp r i n t sv, i d e o ss, l i d e s ,
g i v i n gu p t h e i r fr e et i m et o
basedexplorationof cltnical
supportdevelopmentslikely
c o m p u t e rp r o g r a m sm, i c r o b i a l delivertheactivitymaybe
m i c r o b i o l o g(yS 2 , 9 21 , 7 0 ) .
to leadto an improvementin
s t r a i n so r i n o t h e rf o r m s ,
i n c l u d e di nt h e c o s t i n g s .
"{i*{:*qs,{t!.t
theteachingof any aspect
iiil',i''.;, *,:,r,rtn,
School
s h o u l db e r e a d i l ya v a i l a b lteo
of microbiology
relevantto
A p p l i c a n t s h o u l da l s o
o f B i o l o g i c aSl c i e n c e s ,
Societymemberson free or
secondaryortertiary
i n d i c a t eh o wt h e yw i l la s s e s s U niversityof WalesSwansea:
low-costloanor purchasefor
(includingpostgraduate)
the successof theirevent,
t o r u np r a c t i c a l w o r k s h o posn
a periodof at leastfiveyears
e d u c a t i o inn t h e U K .F u n d i n g
m i c r o b i o l o gi yn p r i m a r y
aftertermination
of the project. (c) Successful applicants
f o r t o u r st o o v e r s e a sh i g h e r
s c h o o l s( S 7 6 5 ) ,
T h e s ef e l l o w s h i phse l p
w
i
l
l
b
e
n
o
t
i
f
i
e
d
i
n
J
a
n
u
a
r
y
t
o
(d)The Societywould
educationinstitutions
to
w o m e nr e t u r nt o t h e i r
facilitatetheirarrangements.
s t u d ym e t h o d so f t e a c h i n g
e n c o ur a g ec o mm e r c i aol r
Pastawards
scientific careersaftertaking
A reportof the activitymust
l a r g ec l a s s e sw i l ln o l o n g e r
o t h e r d i s s e m i n a t i oonf t h e '
The reporlshavenow
a breakforfamilyreasons.
be submittedto the Society
r e s r l t s"o' f i' h
n 'r o i e ct o g
beavailable.
" -e Y
been receivedfor several
Thefellowshipsare normally
w i t h i n3 m o n t h so f t h e
w i d e rp u b l i cA. l l I n t e l l e c t u a l
completedprojects.These
for two years,worth over
Applications
f rom members
completionof the project,
PropertyRights,including
includeDr SarahWatkinson's S I 2000, flexibleas the,
arenowinvitedfor either
T h i ss h o u l dt a k et h e f o r mo f
c o p y r i g hat n dd e s i g nr i g h t s ,
accouno
t f h e r t r i pt o t h e U S A are part-time,tenableat a
categoryof award.The f ull
a n a r t i c l ef o r p u b l i c a t i oinn
i n a n ym a t e r i a l p
s r o d u c e da s
w h e r es h e l e a r n a
t boutthe
rulesof the schemeare
u n i v e r s i toyr a n i n d u s t r i a l
t h e ' G o i n gP u b l i cs' e c t i o n
a resulo
t f t h e g r a n tw i l lb e
laboratorydesignedfor
u s e so f t h e w e b f o r t e a c h i n g
givenbelow.
oI M icrobiology Today,A
rraclor]
in tha Qnniafir
largeclassesand somenovel retrainingand new research
copyof the resultsof the
ffiq*{$*;
^.^^+i^^l
^,,^-^i-^^
i^
and restrictedto science,
a s s e s s m e net x e r c i s e( 2
3. PUSawards
Pr aLLrLdr u Ut LtSe) lt I
m
i
c
r
o
b
i
a
g
l
e
n
e
t
i
c
s
; rMark
e ng in e e rni g a n dt e c h n o l o g y .
1 ,A p p l i c a n tm
s u s tb e
D
s i m p l eq u e s t i o n n a i roer
(a)Applicantsmayseek
members
of the Society,
s u m m a r yo f p u b l i cc o m m e n t s R o b e r t s ' i n s i g hitnst ot h e u s e s A p p l i c a n t s
m u s th a v ea f i r s t
f u n d i n go f n o m o r et h a n
to wh jch computer-assisted
c u r r e n t rl ye s i d i n gi n t h e U K
o n t h e e v e n tw i l ls u f fi c e )
degree,havetakena break
S 1,000 for smallprojects
l e a r n i n gi s p u t i nA u s t r a l i a f o r
o rR e p u b l iocf l r e l a n d .
s h o u l da l s ob e p r o v i d e d .
forthreeyearsand be
t o p r o m o t et h e p u b l i c
teachingveterinary
residentin the U K. Conracr:
2. Practicalteaching aids
bacteriology
and mycology;
J e n ni f e rW o o l l e yT,h e D a p h n e
(a)Applicants
and detailsof the Biodiversity
mayseek
JacksonTrust,Deparlmentof
C o n s o r t im
u Un t t ' s ' M i c r o b i a l
support,
normallywithin the
Physics,Universityof Surrey,
F i e l dT r i p ' C D - R O M
rangeS200-S3,500,for:
G u i l d f o r dG U 2 5 X H ( e - m a i l
developedby Professor
(i)purchaseof consumable
[email protected]),
Johanna Laybourn-Parryand
materials,
but not capital
h e rc o l l e a gu e s .S h o r t e n e d
equipment;
versionsnf ihese rennr[5yyill
(ii)short-termassistance,
appearin M icrobiologyToday
i n d u ec o u r s e .
e.g.vacationemployment
o f a nu n d e r g r a d u a toer,
exceptionally
a postgraduate
afterexpiryof a
studentship.
Non-SGM
award
$il$*s-t't,*r*x$
'Y,r$,s:*'t
i',i'f
${l$t{}{*t.3$"*#YTODAYVOL26l MAY99f
lohn Redwood
MPvis'lts
Marlborcugh
House
ffim&mwwxm&ffiwmmffi
ffimww&wpmwm&
ffiwmd
aimsto assist
Council
indeveloPing
microbiologists
EuroPe
andEastern
countries
theInternational
through
Fund.Awards
Development
aremadebycompetition,
Sax*,p*sm
and
visits(travel
1, Support
bymembers
accommodation)
in
oftheSGMto laboratories
wheremicrobiologY
countries
develoPed
isinadequately
butwhereitsf urther
mayassist
development
of
ortheeconomy
education
ThePUrPose
thesecountries,
ofthevisitsmustbeto give
and
courses
shorllecture
fYTNINO
POSI
ES\RIAOINO
insubjects
training
laboratory
ffia*$dm$6au*s
needs
meetthe
to
designed
The
ofthesecountries.
forsums
1. Applications
mayvaryfromtime- between
countries
S1,000and$5,000
to-timebutatpresentthese willbeconsidered
The purposeof the SeminarSpeakersFundis to promote
first.No
inthe
manyplaces
include
in departmentalseminar
talkson microbiologicaltopics
aboveSZ0O0
applications
.^,1il t-^ ^^^^^+^,]
FarEast,Africa,Southand
Applicationsare invitedfrom highereducation
programmes.
vvlll uu duusPLeu'
theIndian
America,
Central
wheremicrobiologyistaughtfor grantsof up to
institutions
2, Applicantsmustbe
nentandEastern
sub-conti
S2OOtowardsthe travel,and if necessaryaccommodation,
the
Society.
of
members
Host
Europe,
andCentral
expensesof an invitedspeaker.Applicationswillbe dealtwith
lY
areusual
laboratories
on afirsi come,firstservedbasisduringthe academicyear.
3 . I n m a k i n ga p p l i c a t i o n s
some
to provide
expected
Writtensubmissionsshouldbe sentto the GrantsOffice at
for supportfor givingshort
for
of localsupport
evidence
The rulesof the scheme
for consideration,
lecturecoursesor laboratory SGM Headquarters
thecourses.
trarning,detailedinformation aredetailedbelow
must be providedaboutthe
of basic
2. Allowpurchase
1. The schemeis opento highereducationinstitutionsin
relevanceand qualityofthe
forthe
essential
equipment
the U K and Republicof lrelandwheremicrobiologyistaught'
a
n
d
t
h
e
c
o
u
r
s
e
t
r
a
i
n
i
n
g
training
needsof such
Normallyonlyone departmentwithinan institutionwillbe
degreeof localsupportfor
courses.
eligiblefor an awardwithineachacademicyear,whichis
course,
delinedas runningfrom September1999 to June 2000, lt is
journals,
t
Society
3. Provide
expectedthat departmentswillcollaboratein selectinga
4. Eachapplicationmust
andspecial
symposia
semlnars0eaKer.
to established b e a c c o m p a n i e bd y f u l l
publications
periodof s u p p o r t i n gd o c u m e n t s
fora limited
libraries
2. Applicationswtllonlybe acceptedfrom departments,not
orzerocost, 5 , A c o n d i t i o no f f u n d i n g
timeat reduced
f romStudentMicrobiologySocieties.
it
be
can
especiallywhen
(exceptfor provisionof
3. Up to two speakersmay be fundedeachyear,providedthe
shownthatthesepublicationspublications)is that a brief
totalawardto the institutiondoes not normallyexceed5200.
reasonablY r a n n # c r r i l o h l a { a r
arenotcurrently
inthecountry
available
4. Seminarsmust be advertisedregionallyas sponsoredbythe
MicrobiologyToday,be
concerneo,
Society,
provided,
Wwxs*d
mffitrffiWffimkwww
ffiwrcffi
wffiffiwdffiffiffiffi
I v H v ,
$
national
4, Support
e.g.
facilities,
microbiological
(which
culturecollections
microbiology),
underpin
runinto
wherethese
difficulties.
temporary
Applicationsto the Fundare
now invited,Fourcopies,
f u l ls u p p o f t i n g
including
d o c u m e n t ss,h o u l db e s e n t t o
the InternationalSecretarY,
(ProfessorJ,W Almond,
PasteurM6rieuxConnaught,
anyothersmall
5, Support
'1541
A v e n u eM a r c e l
projectto
assistintechnologY
f romWesternEurope M 6 r i e u x , 6 9 2 8 0M a r c y
transfer
above llEtoile,France),
totheareasmentioned
of
forwhichothersources
This
donotexist.
funding
provision
of
mightinclude
a nominated
equipmentto
is
centreatwhicha member
permanently.
working
The closingdatefor
applicationsis 1 October
19 9 9 .
E nn**K$ffiX#hffiffiYTODAYVOL26IMAY99
on receiptof evidenceof
5. Awardswill be paidretrospectively
the actualexpensesincurred.
6. Applicationsshouldcontainthe followinginformation.
(a)The namesand addressesof the speaker(s)to be invited
andthe topicof the talk(s),
(b) Evidence,in the form of a programme,
that an active
semlnarprogrammeis alreadyestablishedin the
Whereno previousprogrammeexists,good
department(s).
reasonshouldbe givenforthe request,suchas the
of a new department.
establishment
It is Councilpolicytopromote
andknowledge
understanding
o f m i c r o b i o l o g i ciasls u e so n
the wideststage.This
i n c l u d e s u b m i t t i n ge v i d e n c e
inquiriesand
to Parliamentary
GovernmentDepartment
andmaintaining
consultations,
contactswith politicianson a
non-partypartisanbasis.
M a d b o r o u g hH o u s e , t h e
Society'sHeadquarters,
l i e si n t h e W o k i n g h a m
parliamentary
constituencyof
the Rt.Hon.JohnRedwood
M B w h o i s S h a d o wM i n i s t e r
forTradeand Industry,
As such,he hasoverall
for scienceand
responsrbilitv
technologyibsueswithinthe
ShadowCabinet,and speaks
on these issuesforthe
Oppositionin
Conservative
lt was therefore
Parliament.
appropriatethat he was able
to visitMarlboroughHouse
o n 1 2 M a r c h , t ol e a r na b o u t
the rangeof SG M'sactivities,
meetthe staff and discuss
mattersof scienceand
educationpolicywith
of Counctt
reoresentatives
and seniorstaff, Matters
coveredincludedthe
importanceof supportfor
basic research,the effects
of excessivemonitoringand
employment
centralization,
conditionsfor academicand
researchmicrobiologists,
i h e i ra b i l i t y t oe x p l o i t
including
f i n d i n g sc o m m e r c i a l layn, d
the roleof the scientifrc
c o m m u n r t iyn g i v i n ga d v i c e
a n dp r o m o t i n gp u b l i c
ng of contentious
understandi
issuessuchas G M food
and BSE,
T h e m i c r o b i o l o g i chailg h l i g h t
of aworking lunchwas
providedby three excellent
cheesesproducedby local
cneesemaKers.
The photographabove
shows(from leftto right)
HowardDalton(SGM
Don Ritchie(SGM
President),
ProfessronalAffai rs Off icer),
(c) Detailsof anysponsorshipfor seminarsthatthe department John RedwoodMP,Ron
Fraser(SGMExecutive
alreadyhas(or is anticipating).
Secretary)and Janet Hurst
(d) An indicationof the targetaudiencefor the seminar,wh ich
(SGM DeputyExecutive
may include u ndergraduatesand postgraduates.
Secretary).
$mm'qp&p$m$qmffig3
$s:r'w
ffi'cp'wmwffp
$l,$wssffiml
ffi,ffiffi
Prize Lecturesand Awalds
-'--...
New
pfOcedUfe
fOf
nominations
ln recentyearsCouncilhas
beendisappointedbythe lack
o f n o m i n a t i o nfso r t h e r a n g e
of prestigiousawardsmade
bythe Societyin recognition
o f d i s t i n g u i s h ecdo n t r i b u t i o n s
to microbiology.lt
has
thereforebeendecidedto
p u b l i s ha n n u a l l yi n t h e M a y
issue of M icrobiology Today
the rulesfor each prizelecture
dueto be awardedin the
followingyear,lt is hoped
thatthis new systemwill
a s s i sm
t e m b e r si n m a k i n g
nominations.The
award
p a n ew
l i l lc o n s i d etrh e
nominations
in the autumn
a n dt h e i rr e c o m m e n d a t i o n s
willbe takento November
The
Councilfor approval,
o u t c o m ew i l lb e a n n o u n c e d
in the Februaryrssueof
MicrobiologyToday.
N o m i n a t i o nasr e n o w s o u g h t
forthe prizelectureslistedon
this page.Anominationform
maybe downloadedfrom the
SGM web siteor obtained
fromthe ExecutiveSecretary
at SocietyHO. Please
compleiethe form andsend it
t o D r C h a r l e sP e n n S
, choolof
BiologicalScience,University
o f B i r m i n g h a mB, i r m i n g h a m
B 15 2TT Dr Pennwillbe
pleasedto discussthe criteria
for nominations,
shouldany
q u e r i e sa r i s e ,
Closingdate for all
nominations:
3 1 A u g u s t19 9 9 .
TheFleming
Lecture
isawarded
annuallyforoutstanding
r e s e a r c hi n a n yb r a n c ho f m i c r o b i o l o gbyy a y o u n g
microbiologist
in the earlystagesof his/hercareer.The
awardisS1,000.
1, N o m i n e e s h o u l dn o r m a l l yh a v eb e e ne n g a g e di n
researchfor not morethan 10 yearsafterdoctoralqualification
or equivalent.
Yearsmaybe addedto thistotalin respectof
careerbreaks,for parenthoodor othersubstantivereasons.
2 .T h e r es h o u l dn o r m a l l yh a v eb e e na c o n n e c t i o n
w i t ht h e
scientificactivityof the Society,eitherby meansof pastand
c o n t i n u i n gm e m b e r s h i op f t h e S o c i e t y( a m i n i m u mo f 3 y e a r s '
membership of the Societywould normallybe expected),or
pastpresentation(s)
at a Societymeetingor publication(s)
in
a S o c i e t yj o u r n a lo, r a n o r g a n i z a t i o noarla d m i n i s t r a t i v e
contributionto the scientificwork of the Societr,
3. Candidates,
who need not be membersof the Societv,
s h o u l ds u b m i ta n o u t l i n eC V i n c l u d i n g
d e t a i l so f q u a l iifc a t i o n s ,
scholarships,
researchgrantsobtained,etc.,a lisiof
p u b l i c a t i o nas n
, o u t l i n eo f t h e i r c a r e epr r o g r e s s i o(np o s t sh e l d
in postdoctoralresearch)andthe namesof two memberswho
aref amiliarwith theirwork,who willbe askedto providea
statementdetailingthe candidate'scontributionto
microbiologyand meritfor the award.Alternatively,
members
w h o w i s ht o m a k ea n o m i n a t i o snh o u l dp r o v i d es u c ha
s t a t e m e nat n ds h o ul d a r r a n g ef o r a s e c o n dm e m b e rw r l l i n g
to supportthe nominationto providea statement,and should
ask the candidateto providethe CV and publications
list,
The GeneralSecretarywillbe pleasedto advisemembers
p r e p a r i n gn o m i n a t i o nasb o u tt h e i n f o r m a t i otno b e s u p p l i e d .
4 .T h e r e c i p i e n t w ibl le e x p e c t e dt o g i v ea l e c t u r eb a s e do n h i s
o r h e r w o r k t oa m e e t i n qo f t h e S o c i e t yw, h i c hw i l lu s u a l l yn o t b e
that whichtakes placein the spring,He or she maybe aikeO Uy
t h e C o u n c iol f t h e S o c i e t v t o r e p e a t t hlee c t u r ea t a n o t h e r
centrein this countryor in Euro'pe.
Expensesof the lecturer
willbe paidby the Society.Requestsfor sucha secondlecture
shouldbe madeto the GeneralSecretaryand willbe
considered
b y C o u n c i lT. h et e x to f t h e l e c t u r ew i l lb e p u b l i s h e d
in either Microbiologyorin the Journalof GeneralVirology,
w h i c h e v eirst h e m o r es u i t a b l eT. h ec h o i c ew i l lb e a t t h e
discretioo
n f t h e E d i t o r so f t h e t w oj o u r n a l s .
5 . I nt h e e v e n to f t h e r eb e i n gn o s u c c e s s f unl o m i n e ei n a n y
particularyear,the Awardmoneywill be returnedto the f unds
of the Society.Any givennomineemaybe chosenonceonly.
.:
:
:
. 1. ' :
The lectureis awardedeveryotheryearby SGM on behalf
oftheInstitute
o f B i o l o g yf o r a n o u t s t a n d i n cgo n t r i b u t i otno
researchin a moreapplilOareaof microbiology,
or in an area
w h e r em i c r o b i o l o gi ym p i n g e so n o t h e ra r e a so f b i o l o g ya,n d
wherethe topicwouldbe attractiveto a widerbiological
a r r d i e n c eT h e n r i z ei s 9 . 5 0 0 C
. o n t a c tC h a r l e sP e n nf o r
f u r t h e rd e t a i l s .
4 . T h er e c i p i e n t otfh e
Malory StephensonPrize
Lectureshipwillbe expected
givea lecturebasedon
St*'$xg,r &,,$:l$ti!.$
i:'tjl to
the work for whichthe Prize
Lectureshiphas been
awardedto a meetingof the
T h ef i r s tc a l lf o r n o m i n a t l o n s
S o c i e t yn, o r m a l l tyh e S p r n
ig
w a sp u b l i s h e d
i nt h e F e b r u a r y
m e e t i n gf o l l o w i n gt h e
issue of Microbiology Today
announcementof the award.
( V o | . 2 6p, . 2 3 ) .P l e a s en o t e
T h e r e c i p i e nwt i l lb e s t r o n g l y
t h a t t h ec l o s i n gd a t ef o r
encouraged
t o p u b l i s ht h e
n o m i n a t i o nhsa sb e e n
lecturein either Microbiology
c h a n g e dt o f i t i n w i t ht h e
or the Journal of General
new procedure.
Virology,whichever
is the
m o r es u i t a b l eT.h ec h o i c ew i l l
Rules
be at the discretionof the
1. The MarloryStephenson
E d i t o r so f t h ej o u r n a l s .
PrrzeLectureshallbe
a w a r d e db i e n n i a l lfyo r a n
o u t s t a n d i n cgo n t r i b u t i oonf
currentimportancein
L*iI,{,:{s*frY*f'
microbiology,
without
restrrction
on the areaof
microbiology
in whichthe
awardis made,
T h e 1 9 9 9 F l e m i n gL e c t u r e
has beenawardedto
2 . N o m i n a t i o nfso r t h e
D r D a v i dR i c h a r d s o nS,c h o o l
MarloryStephensonPrize
o f B i o l o g i c aSl c i e n c e s ,
Lectureshallbe madeby any
Universityof EastAngiia,in
two membersof the Society;
r e c o g n i t i o on f h i sc o n t r i b u t r o n
t h e n o m i n e en e e dn o t b e a
t o t h e u n d e r s t a n d i nogf
mamhornf
*ho
Qnnial,,
f u n d a m e n t apl h y s i o l oigc a l
N o m i n a t i o nssh o u l db e
and molecularaspectsof
accompaniedby a statement
bacterialrespiration.
Theiitle
o f t h e c o n t r i b u t i otno
o f h i sl e c t u r ew, h i c hw i l lb e
m i c r o b i o l o gm
y a d eb yt h e
deliverea
d tt h e S o c i e t y
n o m i n e es, u p p o r t e db y
meetingat the U niversityof
r e p r i n t so r o t h e ra p p r o p r i a t e I o o d q i n S c n t o m h a r l O O O i c
d o c u m e n t a t i oA
n ,b r i e f
Bacterial respi ration: a
curriculum vitaeof the
flevihle
nrnra<c
f^r a
n o m i n e ea n da f u l l
changing environment.A
b i b l i o g r a p hoyf h i so r h e rw o r k
p r o f i l eo f D r R i c h a r d s ow
n ill
s h o u l da l s ob e i n c l u d e d .
a p p e a ri n t h e A u g u s ti s s u eo f
3. Thereshallbe no restriction Microbiology Today.
by meansof age or nationality
o f t h o s ee l i g i b l ef o r i h e
Malory StephensonPrize
I ectrrre Rer-inients
nf the
Lectureshipmaynot be
nominated
ona subsequent
occasion.
jgfrs$t
*!utt*r
rx$.tE*,{t
1
t {,}S{;}r
&mmffiw.mffiffi
%ffiffiffi
Meetings on
the web
Uo-to-dateinformation
on futureSociety
meetingsis availableon
the web site http://www.
socgenmicrobiol.org,uk
144th Ordinary Meeting
UniversityofLeeds
7-lOSeptember
ffi S S*ptemh*r
fuiX
*i**r"rIsrMa*h ir"l** : h4*:b ile Fr*t* in S*m $ lex*s
in hdi*r*-nrgnni*ms
published
of
issue
intheFebruary
were
ofmany
ofthesymposia
Details
aboutthe
sitef0rfull
information
web
28-29),
See
Microbiologyloday(pp
ifyou
pr0gramme
abooking
form
and
todownload
occur
asthey
changes
ofthis
magazine,
onp.99
touse
theone
donotwish
Group
&Molecular
Genetics
Biochemistry
Physiology,
(lizsockett@nottingham
ac.uk)
LizSockett
0rganizer:
prizewinner
and
J Walker,Iitles
istheNobel
inthissession
Aspeaker
papers
should
besent
totheorganizer
andposters
abstracts
foroffered
1$99
by1June
$ynrp*siurn{7*S S*pt*mb*ri
& fu4min
fvlmrnhr*ns*? W S*1 i) $cpten"rb*r
H*w ffic hX*i**ul** {)r*n* hdiE:r*bial
r'fa** ffiimsph*r*
t)*ep $ ubsn"*
p,74forapreview
ofthe
formSee
inbook
willbepublished
symposium
This
jointly
withthe
Microbiology
Group
Environmental
The programmesof
topics
tobecovered.
Group
Society
Marine
Studies
Geological
the Society'smeetings
(j.parkes@bristol,ac
uk)
J,Parkes
0rganizer:
are organizedbythe
O OTHERSYMPOSIA
(young
papers
posters
scienti$s
and
ab$racts
for
offered
Iitles
and
committeesof the
? $*pt*mb*r
S
particularly
1
19$$
sent
to
the
organizer
by
June
welcome)
should
be
specialinterestg roups,
T*n*hing M i*r*i:i*l*gy t* N*n-rni*r*bi*i*gr*tx :
co-ordinatedbythe
tl:e thallcng* *{ hd*d*larStrx*tur*x
O SPECIAL EVENTSFORYOUNGER MEMBERS
ScientificMeetings
Group
Education
Officer,Dr PatGoodwin,
& ? S*pt*nrL:*r
(osullih@livhope,ac,uk)
Helen
0'Sullivan
0rganizer:
Fr-ornega
Suggestionsfor topicsfor
PriaeFinal
Meetingg
organization
futuresymposiaare
alwayswelcome.See
o,95 for contactdetails
of GrouoConveners.
of
Administration
meetingsis carriedout
b y M r sJ o s i a n eD u n no f
the MeetingsOfficeat
W 7*S S*pt*mb*r
ng
fi *il Lysi*in Ferm*nta{i*n *nejffii* g:rccessi
Group
&Bioprocessing
Fermentation
(UK)Ltd
Scientific
Brunswick
byNew
Sponsored
Rob
Cumming
0rganizer:
papers
besent
t0
should
orposters
foroffered
and
ab$racts
Titles
(r.england@uclan,ac,uk)by
1June
1999.
Fngland
Reg
SGM Headquarters,
MarlboroughHouse,
BasingstokeRoad,
S S*1 * Sept*mb*r
F**d-b*rn* i nfc*ti*n* *r:d $nt*xis:ati***
Abstracts
book
& # $cpt*mh*r
Aeih**iv*Str*r:tur**
inscientific
toencourage
excellence
sponsors
thiscompetition
Promega
judged
have
now
the
scientists,
Group
Committees
byyoung
communication
presentations
2Brelated
torecent
Group
bymembers
under
orposter
oral
goforward
inaspecial
forPromega
Prizes
finalists
tocompete
symposia
The
atLeeds
There
aretwo
ontheir
research
ofshort
oralpresentations
session
prizes
forthe
and
thewinners
willgoontocompete
each
tobewon
of1200
from
other
theYr,arin1l}}again$finali$s
LifeScientistof
IilleolYoung
societies
learned
Y*ung*r {\,4em
bcrs' ffi***pti*n
event
for
there
willbeaspecial
following
thecompetition
Intheevening
- po$grads
presentation
younger
onCVs
andpostdocs,
Ashort
members
Evolution/
lnfection/SystematicJa
Microbial
SpencersWood,
a
and
finger
buffet
For
byawine
reception
willbefollowed
andInterviews
Groups
Genetics
&Molecular
Biochemistry
Physiology,
R e a d i n gR G 7 1 A E
inpromoting
tobeasskilled
inmicrobiology
itisnecessary
successful
career
jointly
Society
withThePathological
- thissession
T e l . 0 11 8 9 8 8 1 8 0 5
your
yourself
willprovide
research
findings
ascommunicating
andNiall
Logan
Adrian
Eley
Fo$er,
lanPoxton,
Simon
0rganizers:
F a x0 1 1I 9 8 8 5 6 5 6
mu$
willbebyticket
only
which
event
isfree,
butentry
invaluable
advice,
The
papers
lanPoxton
should
besentto
andpo$ers
foroffered
Titles
andabstracts
e-mailmeetings@
Westwellat
registering
forthe
meeting
ContactJane
bebooked
when
(i.r,poxton@ed,ac.uk)
1999.
by1June
socgenmicrobiol.org.uk
House
fordetails.
Marlborough
EdinburghMeeting
April1999
Thef ulltextof the
bookis now
abstracts
asa PDFfile
available
ontheSGM website.
E
O OFFEREDPOSTERPAPERS
po$er
papers
and
ofmicrobiology,Iitles
areinvited
onanyaspect
Offered
(including
0ffice
at
should
besent
totheMeetings
fulladdresses)
authors
than
1June
1$99.This
date
isearlier
toarrive
nolater
than
Marlborough
House,
atthis
ab$racts
should
also
besubmitted
advertised
lfpossible
thatpreviously
bye-mail
for
lhan
30June
1999andbesent
should
arrive
n0latsr
stage;
these
publication
ispermitted
book.
Amaximum
of200words
intheab$racts
Group
&CellSurfaces
Cells
(prsaws@bath
Mike
Wilson
acuk)and
Smith
0rganizers:Anthony
(mwi
k)
lson
@eastmand.ucl.ac,u
papers
should
besent
tothe
andposters
foroffered
Titles
andab$racts
inthe
forresearchers
opportunity
1999.This
isanideal
organizers
by1June
their
work,
adhesion
topresent
ofmicrobial
aspects
and
functional
$ructural
presentations,
slots
free
for
oral
two
there
are
currently
arewelcome;
Posters
ffins&g,xrw
ilWww&$mgm
(FBP
treatment
Group
&SfAM)/
SPRING 2OOI
proteolysls
Proteases,
andcontrol 148th Ordinary
(PBMG
&CCS
Groups.
0rganizers: Meeting
C,Stirling
colin
stirling@
man.ac
uk 24-30 March2001
&D,Hodgson
[email protected]
warwick.Heri ot-Watt -University
ac,uk)
/ Public
education
insafe
food
& l\tlain$ymp**ium
and
water(Ed,
Group
0 SfAM
# MainSynrp**iuni
N*wf;hallcngc*to
0rganizer:
R,Bishop
rh.bishop@ul$
Lifeor ffi*ath*f affell
FightingInfe*ticnintl'rs
l-'le#th: th* Threatcf
ac.uk)
/ Transcriptional
control
circuits
*1mt**ntury
Viru*
Infe*tietn
Virus
andClinical
Virology
Groups
infungi(PBMG
Group
0rganizer:
0rganizer:Geoff
putlished
Smith
0rganizers:
PGoodwin
PAndrew, A,Brown
To
le
al,brown@abdn.
acuk)/
(glsmith@molbiol,ox,ac,uk)
G.Smith,
DStewart-Tull,
MEa$er Vaccine
(MlGroup,
delivery
Smith
0rganizer:0rganizer:Geoff
(Cambridge) and
0ay
1:A,
Wyllie
P0yston
poy$on@
P0y$on
ac.uk)
hotmailcom)/(glsmith@molbiol,ox
Overview
ofapoptosis
/ D,McCancePre$igious
speakers
from
around Virus
(VGroup
entry
and
exit
(Roche$er,
USA)
HPV
/ LWileman theworld
including
aUKgovernment
glsmith@
0rganizer:
GSmith
(Pirbright)
ASFV
/ HThomas
representative
andspokesmen
from molbiol,ox.ac
uk)
(StMary's
London)
HBV
/
WH0,
willcover
thefollowing
topics: Also:
Evening
workshops,
social
(USA)
AGreenberg
Lessons
from
CILand
thesuccesses
and
events
and
trade
exhibition
papers failures
apoptosis
/ 0ffered
oral
ofglobal
vaccine
Further
details
ofallsymposia
are
(Birmingham) programtnes
Gommercialization
[ay2:PGallimore
/ Iheglobalthreat
of
available
ontheSGM
web
siteand
will
of Microbial
Adenovirustransformation
/ W.Wold emerging
infectious
diseases
/ The bepublished
inthenext
issue
of
(StLouls
Biotechnology
USA)Adenotlirus
apoptosis
/ worldwide
epidemic
ofantibiotic- MicrobioIogyIoday.Wher
en0nam
es
(Birmingham)
16-17 September1999
L,Young
EBV
resistant
i
bacteria
/ Protecting
farm ofsymposia
organizers
aregiven
(Chester
University
of Ulsterat
C,Boshoff
Beatty
London) animalsfrom
infectious
disease
/
please
above,
contact
theappropriate
(Erlangen, Can
Coleraine
HHV-B
/ B Fleckenstein
moleculartechnioues
have
arole Group
(see
Convener
forinformation
ForJurther
information
and
tooffer
HVS
Germany)
/ 0ffered
oralpapers inthenrevention
ofcontamination
of p 95foraddreses)
papers
po$ers
(Madison,
processed
and
pathogens?
contact
Nigel
[ay3(am):
PFreisen
food
by
USA)
/ New
(ng.ternan@ul$,ac
(StMary's approaches
iernan
uk),
Baculovirus
/ C.Bangham
topublic
education
inthe
See
also
theSGM
web
site
London)
HILV-1
/ J Fazackerley prevention
ofcommunicable
disease
/ AUTUMN 2OOO
(Edinburgh)
Alphaviruses
/ H-J,Ihiel lsglobal
clean
water
attainable?
/ The l47th Ordinary
Meeting
(Giessen)
BVDV
useofmicroassays
inunderstanding
12-15 September2000 Recent Advances in
papersinfections
Titles
and
ab$racts
f0roffered
andindiagnosis
/ Live
Molecular Microbial
promiser Universityof Exeter
oroosters
should
besent
tothe
attenuated
vectors
/ The
Ecology
organizer
by21September
I gg9,All ofDNA
vaccination
/ Vaccine
S tVlain
$ympesium
7-8A pri l 2000
submissions
should
contain
the
development
/ lmmunotherapy
of
C*rxmunity$tructure
UniversityCollege,
names
ofallauthors
their
affiliations,
infectious
cancers
/ Vaccine
and to-op*ration in
Galway
paper,
thetitle
ofthe
thename
ofthe production
inplants
/ Iherapeutic ffir*films
zuthorwho
willmake
thenresentation
antibodies
against
endotoxaemia
and lotepatlished
Titlet.b.a.
and
whetherthey
areeligible
for
sepsis
/ New
$rategies
foridentifying
0rganizer:
Hilary
Lappin-Scott 'Autumn2000
consideration
foraPromega
Prize anddeveloping
new
antimicrobial
(h,m,[email protected],uk)
(see
p,89)togetherwith
NationalUniversityof
anabstract drugs
/ Aremolecular
methods
the
symposia:
Applications
of
lreland,Maynooth
tcu\,V0r0s)
optimum
route
toantimicrobial Other
tmaxllllum
recombinant
technology
toindustrial
[ttetlin0Workshops
drugs?
/ Prospects
foranew
and
/ Biofilms
ininfection
hfluenzaVirus
arediscovered
form
oftherapy: fermentations
Fordetailsof lrish
anddisease
/ Control
ofbiofilms
/
probiotics
phage
0rganizer:
John
McCauley
and
Branch
activities
Mathematical
skills
and
(john,[email protected]
uk)
Totepublished
contactthe
Convener,
microbiolooists
[xotbViruses
()ther
MartinCollins
symposia:
Microbial
ecology
0rganizer:
Susan
Jacobs
([email protected])
offood-poisoning
micro-organisms
(jacobs_susan@
hotmail
com)
(EM
Group
&SfAM.
0rganizer:
Anyone
wishing
toparticipate
in
Linda
Lawton
[email protected],uk)
/
workshops
should
contact
the
Molecular
epidemiology:
sub-specific
organizer
nolatsr
than
classification
and
identification
1g9g,
(SE
&CVGroups)
/ Potable
water
wtNTER 1999/2000
| 45th Ordinary
Meeting
5-7 January2000
Universityof Surrey,
Guildford
*
OVirusInfectran
SPRING 2OOO
Millennium Meeting
10-14April2000
UniversityofWarwick
(jointlywith Societyfor
AppliedMicrobiology)
ffimXwk
ffirmmGh
journalist &wwkmwffi
trffifu$w$wggw
ffiKWffi
ffi ffiffi&ffi
$wWW
Science
takes
MerielJones
G.M.TavlotM.Goval,A.J.Legge,R'J.Shaw& D.Young
a lookat some
of tests,theauthorscould
for hospitals
developed
isoneof the
Tuberculosis
papersin current
seethat M,tuberculosis
of
to identifysub-groups
of
ancientscourges
issuesof the
DNAfrombonesofone
thecausalbacterium
lt isstillafeared
humanity.
journals disease,althoughit isnow Mycobacterium tubercuIosis youngmanhadsubtle
Society's
f rombacterial
differences
andto checkantibiotic
rareinthe U K andusually
w h i c hh i g h l i g h t
DNAinanotherman's
DNAisa
sensitivity.
withantibiotics,
treatable
exciting
newand
Thisholdsoutthe
bones,
persistent
Althoughthe mostfamiliar remarkably
in
developments
of tracking
anda collaboration prospect
molecule
of TB are
symptoms
microbiological damagetothelungs,ina
of
individualstrains
and
of medicalscientists
thediseasethrough
istshavenow
archaeolog
casesit
research,
smallnumberof
of
theiranalyses
reported
attacksbones,This
verycharacteristic DNAfrombonesinthe
produces
of theAbbeyof
graveyard
scarsthatlastaslongas
St MaryGraces.Thiscentral
Thisenduring
thebones.
Londoncemeterywas
damagehasbeenusedto
foundedin 1350 anduseo
spread
studythehistorical
of
untilthedissolution
of TB bothamonghuman
byKing
andbetween themonasteries
communities
H e n r y V l l l i1n5 3 B , T h e
peopleandtheirdomestic
foundM.
researchers
Indeed,
one
animals.
DNA in bones
tuberculosis
fortheoriginof
hypothesis
bearingTB scarsandnotin
thehumandiseaseisthat
about15,000yearsagoone boneslackingthesesigns,
thattheDNA
indicating
strainspreadfromnewly
hadnotbecomescattered
cattleand
domesticated
duringthecenturies,A
goatsto people.
quickcheckforevidence
arenowhoping
Scientists
modern
of resistanceto
to getclearerinformation
antibioticsshowed
hospital
abouttheoriginandspread that,asanticipated,these
applying
ofTBthrough
have
oldbacteriawould
biological
molecular
beensensitive.After
Thesehavebeen
methods.
workingthrougha series
communities
long-dead
ical
andtaking archaeolog
to anexciting
epidemiology
newlevel,
I Genotypic analysis of
My cobacterium t ubercuI osis frcm
medieval human remains.
MicrobiologyI45, 899-904.
fuw.wmk
&Wm*m$
N.Lea.J.M.Lord& L.M.Roberts
coliOl57 hasmadea placefor
s Escherichia
Theinfamou
lethalformof food
itselfasthecauseof a particularly
have
Wanruick
attheUniversityof
poisoning,
Researchers
howoneof itstoxinsworks.This
beentryingto understand
bythebacteriathat
toxin,calledSLT-1, isa proteinreleased
clingsto thesurfaceof gutcellsandthenentersthem.Once
of thecellmakesthe
inside,
oneof thenormalconstituents
fatalmistakeof cuttingthetoxin,Thislethalfragmentthen
withinthecelland
withnormalproteinproduction
rnterferes
the resultisdeath,
icargumentaboutthe importance
Therehasbeena scientif
havedetectedtoxic
Somescientists
of thisf ragmentation.
the levelcertainly
although
beforecleavage,
activity
membersof the
Others,including
afterwards,
increased
Warwickgroup,havemadechangesto thetoxinthatshould
it beingcut,andthenrecordednodecrease
haveprevented
thatSLT-1 canbe
Thishasledto speculation
intoxicity.
oneplace,
in morethan
snipped
what
havenowreported
MichaelLordandhiscolleagues
whentheyworkedthroughthetoxin
happened
g everypossiblecleavagesite'They
lyremovin
systematical
of toxinfor bothcleavage
thentestedthesenovelversions
cells.The
andtoxicityto mammalian
bycellenzymes
Thetoxinindeedhadtwo possible
outcomewasquiteclear,
thecells
sites,Oncethesewerebothremoved,
cleavage
of
thisintactversion
couldnolongercutthetoxin.Although
cleavableversions
SLT-1couldcausesomedamage,the
wereverymuchmoretoxic.
I Proteolytic cleavageof the A subunit is essential for maximum
cytotoxicity of Escherich ia coI i OItT : H7 Shiga-like toxin- 1.
Microbiology 145, 999 -1004.
VOL26/MAY99
ffiffmwwfuww
ffmwww
&ffimw
dwwp
kffiwwffiwffi
h
meetingthe bacteriathat
live
Microbiologists
aregradually
sea,IntheApril1999 issueof theIJSB,
deepunderthe
andarchaeafromtheseabed
threenewspeciesof bacteria
onespecificgroupwere
anda newmethodfor identifying
interest
fromscientists
described.
Thereis increasing
worldwide
inthe biology,
chemistry
andgeologyof deep-sea
wherewe canlearnmoreabouttheformation
environments,
diversity
of life,
of thecontinents
andthe incredible
ffi
(Marteinsson
An internationalgroup
etal) hasfoundone
at 4OOtimesnormal
soeciesthatlikesitsseawater
pressure
atmospheric
attemperatures
of upto98 "Cllt
ventat a
camefromsamplestakenfroma hydrothermal
Ridgebythe
depthof 3550 m inthe Mid-Atlantic
Alvinin1993,Boiling
waterandrock
submersible
fragments
eruptheref romtheseabed.
Onceatthesurface,
in pressurized
thesampleswerekeptoxygen-free
syringes
dilutionleftthescientists
withone
ina hotoven,Repeated
thatgrewfastestinthevery
spherical,
swimmingbacterium
Thegrouphasnowreported
hot,high-pressure
conditions,
muchmoreaboutitsnature,lt turnsoutalsoto beableto
(only3 timesatmospheric
growat muchlowerpressures
(75'C),althoughnotsowell,
pressure)
andtemperatures
Thermococcus
barophilugastheyhavenamedit,isa
possesses
memberof thedomainArchaea.lt
thefattyacids
apparatus
uniqueto thisgroup,alongwitha characteristic
forproteinsynthesis,
Thearchaeahavesomefeaturesin
withanimalcells,
alongwiththeirbacterial
common
probably
resemble
characteristics,
Theseorganisms
the
lifeonthisolanetandareconsidered
bvsometo
earliest
beaseparate
kingdom,
Although
thisspeciescomesfromtheocean'sdepths,
group(Takaietal) hasmanaged
to isolate
aJapanese
anotherone,whichwascalledThermaerobacter
marianensis,frommudontheworld'sdeepestseaf loor.This'
is 10897 m belowsealevel(yes1 1 kmdeep!)intheMariana
Trench
Challenger
Deep,off Guamlslandinthe Pacific
wasthat
Ocean,
Oneoddaspectof itsgrowthrequirements
despite
comingf romsucha high-pressure
environment,
notgrowwhenthe
Thermaerobacter
marianenslswould
researchers
putit intopressurized
containers.
Thislong,thin,
required
rod-shaped
bacterium
seawater,
oxygenanda
temoerature
around75'C,
Perhaps
inspired
bythedifficulties
of identifying
organisms T H IPSA G E r
(alka
The
unmanned
submersible
fromtheextremeenvironments
mentioned
above,intheir
used
forcollection
ofsamples
from
the
secondpaperinthe issue,Jeanthon
ef a/.described
a rapid deep
trenches
ofthePacific
0cean
methodfor identifying
hyperthermophilic
methanococci.
lt
COURTESY
KEN
TAKAI.
JAII/STEC
(PCR)to amplifya
exploits
the Polymerase
ChainReaction
regionof genesknownto containfeaturesuniqueto
O P P OP
SA
I TG
TEO
E P:
Freeze-fracture
electron
micrograph
of
methanogens;then,
usingenzymes
thatcuttheamplified
Methanococcus
vulcantus
slratn
l,lll, a
DNAintoseveral
chunks,
theorgansims
canbe identified
by novel
hyperthermophilic
methanogen
-this isalsoknownbytheratherlongthepatternproduced
isolated
from
theEast
Pacific
Rise
windedtongue-twister
Restriction
FragmentLength
COURTESY
C,JEANTl]ON,
CNRS
ROSCOFF
(RFLP).
Polymorphism
Theaccuracy
of thenewmethod
wasdetermined
bycomparing
predicted
andactualpatterns O P P O SPIAI EOBEO T T O [ / :
S p i ntaul b e r c u l oLsai rsgcea v i t a t i n g
fromknownmethanococci,When
Jeanthonef a/.tried
this
l y t i lce s i o n
i nst w oa d j a c el unm
t bar
outonmethanogens
obtained
fromasfarapartasthe Midv e r t e b frraoem
a m a laeg ebde t w e1e5n
AtlanticRidgeandthe EastPacificRise,they
couldidentify a n d2 5y e a rastt h et i m eo fh i sd e a t h .
The
s a m p lw
ee
s reex c a v aftreodm
the
somesoeciesthathadaworldwide
distribution,
Considering
the largenumberof microbes
thathavebeen
foundonthe Earth's
surface,
culturing
andidentification
maycontinuewellintothe nextmillennium
beforethese
inhospitable
yieldthetruediversity
deep-seahabitats
of
theirinhabitants.
I V.T. Marteinsson,J.-L.Birrien, A.-L. Reysenbach, M. Vernet,
D. Marie, A. Gambacorta, P. Messner, IJ.B. Sleytr & D. Prieur.
Thermococcus
barophilussp. nov., a new barophilic and
hyperthermophilic archaeon isolated under high hydrostatic
pressure from a deep-seahydrothermal vent.lntJ Sy:tBacteriol49,
largegraveyard
overlying
thesiteofthe
o l dR o y [a/ li n tL, o n d oTnh e
cemetery
w a sa s s o c i awt ei tdh
t h eA b b eoyfS t
I t / a rGyr a c et hse,l a sC
t istercian
foundaiion
in England
founded
in 1350
A DG e n o t y ps iunggg e d
s ti s e aws a
es
d u et oa s t r a irne s e m bpl irnegs ednat y
Mycobacteriun tubercuI osis ratherthan
Mycobacteriun
bovis.
COURTISY
i\/ICHAEL
TAYLOR
35r-359.
IC.Jeanthon,
S. I-Haridon, A.-L. Reysenbach, E. Come,M.
Vernet, P. Messner, IJ.B. Sleyr & D. P tieur. Methanococcus
nutritional
Boththeseorganisms
havefairlyconventional
uulcaniussp. nov., anovel hyperthermophilic methanogen isolated
relyingon a mixtureof proteins,
requirements,
sugarsand
from East Pacific Rise, and identification of Methanococcus
sp. DSM
vitami
ns,However,marinebacteriacanhaveverydifferent
427 3T asM ethanococcus
feruenssp. nov. I ntJ Sy st B acta i oI 49, 5 83 -5 89 .
needs.
Thereisonedistinctgroupthatcanuseonlycarbon
I C. Jeanthon, S. I- Haridon, S. Pradel & D. Prieur. Rapid
generating
dioxide
assourcesof energy,
andhydrogen
gasasawasteproductInthefirstof two papersin identifi cation of hyperthermophilic methanococci isolated from
methane
theissue,
Jeanthonef a/,identifiedtwo newspeciesof these deep-seahydrothermal vents. lntJ SlstBacteriol49, r9I-594.
methanogen
vulcaniusand
so-called
s,Methanococcus
I K. Thkai, A. Inoue & K. Horikoshi. Therrnaerobactanarianensis
Methanococcus
fervens,from
hydrothermal
chimneysinthe gen. nov., sp. nov., an aerobic extremely thermophilic marine
bacterium from the 1 1000 m deep Mariana Trench . lnt I Sy$Baaeriol
EastPacific RiseandGuayamas
Basin,morethan2000 m
49,619-528.
Again,theseorganisms
prefer
beneath
thesurface.
forgrowth,andthis
extremes
of temperature
andpressures
isreflected
intheirnames:vulcaniusrefers
to Vulcanus,
the
Roman
firegod,and fervensmeans
boilinghotin Latin,
ffi $ffiffi#ffi $#tuffiffiYIoDAYVOL26/MAY99 E
Microbiology
Strcptomycete
special issue
career
Tohonourthe
SirDavid
of Professor
Hopwood,Microbiology
i sp u b l i s h i nags p e c i ai sl s u e
of thejournalinautumn
1 9 9 9i nw h i c hm a n y otfh e
oaoerswillbedevotedto the
genetics
andmolecular
biologyof streptomycetes
andrelatedactinomycetes.
w i l li n c l u dae
T h i si s s u e
reviewarliclebyDavid
Hopwood(Fortyyearsof
genetics wtth Streptomyces:
from in vivothroughin vitro
wellas peertoin silico),as
papers
research
reviewed
groups,
fromleading
and
Forf urtherinformation
seeourweb
anorderform
siteat http://www.socgen
microbiol.org.uk
R,Aaziz&M.Tepfer
knowledge
aboutthis
topicandhaveconcluded
thatwestillknow
littleaboutthe
surprisingly
details,
Experiments
are
generally
designedto select
recombinant,
and
of advantageous
oneparticulartype
theouantitv
of minoranddeleterious
so underestimate
vanants,
Vrruses
areastrangeformof life.Theyarestrippeddown
a
canrecognize
of a containerwhich
tothebareessentials
to
hostcellandthenreleasea setof geneticinstructions
fungusor
plant,
inananimal,
it,Thiscell,whether
subvert
and
ignores
itsnormalduties
immediately
bacterium,
replicating
thevirus,Thenewvirusescanthen
commences
theirexhausted
hostcellsleaving
traveltonewunsuspecting
willusually
Thissortof activity
behind,
or deadbenefactor
andonethatcanbeverydifficulttotreat
resultina disease,
carriedout
areactually
becausemostof thevirus'activities
of thehealthyhost.
byihenormalconstituents
areonly
populations
of RNAviruses
Thesechanging
inthe
viableorganisms
resiricted
bytheneedto maintain
Theauthors
pressures.
faceof environmental
selection
naturalshufflingmayhave
pointoutthatthiscontinual
implications
fora newtypeof virus-resistant
ecological
haveachieved
thistypeof cropby
crop.Plantbreeders
plantscontaining
aviralgene.The
transgenic
constructing
in
plantsweredescribed
f irstvirus-resistant
transgenic
impact
thinkabouttheir
1986 butit isparticularlytimelyto
havealreadybeenlicensed
nowbecause
threevarieties
useintheUSA,
forcommercial
,ii,$xs,'.$
W$p'*"uwws
we cannotknowthe
Theauthorspointoutthatalthough
theverylargeamountof a
f requency
of recombinatron,
cropsuggeststhatevenrare
commercialvirus-resistant
plantrecombination
eventsarelikelytohappen.The
produced
viralRNAwrllinevitably
beencountered
sometime
The
virusduringitsowncopying
cycle.
byaninvading
with
scenarios
authorsthereforego onto explorepossible
thatcouldarise,
Since
theemphasis
on hazards
plantsareinfected
recombination
occursnaturallywhen
mustbe
withdifferent
viruses,
theemphasis
simultaneously
areknownto have
ThelargegroupcalledRNAviruses
noveltypes
of virus
whetheranycompletely
ondiscovering
organism
copiesits
Wheneveran
manymutantversions,
duringinfection
of avirus-resistant
canbe produced
of thenewset.The
genes,it needsto checktheaccuracy
mightbethe
plant.The
mostworrying
situation
transgenic
indeedgainfrom appearance
havenowayofdoingthis,and
RNAviruses
of newviralstrainswithnewpropedies
creepin.Whatismore,if two
theerrorsthatinevitably
intheenvironment,
persisting
to beclosetogetherwhen
happen
RNAviruses
different
reports
haveonlyfoundafewexperimental
Thereviewers
copyprocesscanget
theyarecopyingthemselveqthe
Forexample,
tobaccoplants
thesepossibilities.
exploring
whichisa
ina newrecombinantvirus
resulting
confused,
forviralmovement
throughout
a geneessential
expressing
between
mrxture
of both.Thef irstrecordof recombination
wasrepodedin 1962 fromacultureof human the planthavebeeninfectedwithmodifiedvirusesinwhich
RNAviruses
Althoughrecombi
nantviruses
Athirdstrainwith thisgeneis inactivated.
cellsinfectedwithtwostrainsof poliovirus.
moreseveresymptoms
noneof themproduced
fromthecells, appeared,
mixedfeaturesof itstwo parentswasisolated
new
thanthe normalvirus.Inanoiherseriesof experiments,
Therehavebeenmanymorereportssince.Although
viruseswereoroducedinthetest-tubethat
recombinant
canoccurbetweenregionsof genesthat
recombination
when plantswereinfected.
gavenovelsymptoms
it alsohappensbetweenareaswithno
areverysimilar,
withtheoriginal
therewasnocomparison
Unfortunately,
obvious simiIarity,Rachid AazizandMarkTepferf rom
only
viralstrains,
sincein reallifeanynewrecombinantvirus
current
France,
havebeenreviewing
lNRA-Versailles,
overotherstrains.
persists
if it hassomeadvantage
onegoodwaytoprevent
thatinfectplants,
Forviruses
f ungior
theinsects,
to eliminate
isio usepesticides
disease
thatspreadthevirusf romplantto plant.An
nematodes
intocommercial
crops,
isto breedresistance
alternative
Theproblem
thishasoftenprovedimpossible,
although
geneexists,
orwhenit proves
ariseswhenno resistance
the
it intothecrop,Inaddition,
introduce
impossibleto
virusescankeepaheadof theplantbreederthrough
intonewversions.
andrecombining
mutating
information,the
the limitedpublished
Afterevaluating
theythinkwouldpermit
authors
outline
theexperiments
transgenic
propersafetyevaluation
of virus-resistant
The lnternationa I lou rnal ofSyste m atic
plants,
betweeneventsin
Thekeyonesarecomparisons
Bacteriologyis publishedquarterlyon behalfof the
plantsinfectedwithtwovirusesand
non-transgenic
withtheICSB,
IUMSinconjunction
transgenic
plantsinfectedwitheachvirus
virus-resistant
shouldshow
A seriesof theseexperiments
atconcessionary separately.
SGMjournals
Membersmaypurchase
millions
of
whetherresultsarethesameasoverprevious
Officefor
rates.Seep,49 or contactthe Membership
yearsorwhethersomething
quitenewhappens,
details,
two monthlyjournals,
TheSGM publishes
M i cro b io logy anoI o urn a I of G en e ra I Virology.
AB0VET
As c h e m ar et rpcr e s e n toaft i o n
r aRl N a
An d
r e c o m b i nb
ae
t i townevei n
t r a n s gm
e nReNsAu p e r i m poons e d
photos
from
napus
leaves
ofBrasstca
resista
t rnatn s g epnl a
i cn(t lse f ta) n d
s e n s i tni v0en - t r a n s gp el anni (ct rsi g h t )
e dl t h
b o tohfw h i chha db e einn f e c tw
isavailable
subscriptions
Information
on commercial
ttlrnm
i p o s api co t y v r r L l s
INRA.VERSAITTTS fromtheJournals
XIARKTEPFER
SalesOffice.
COURITSY
J
si tu{*{ ;-*roDAYVOL26/ MAY99
E pSgwr-es.FF4$
I Recombination in RNA viruses and in virus-resistant transsenic
plants.J G enViroI 80, B 39-I 346.
ffiffiffiffiffi
Life
E,coliaids
the Younu
of
fight
against Scieitist
Year
sun0urn
Frurnega
ul(
Promegasponsorsan annualcompetitionto encourageyoung life scientistsand to promote
Vacation
studentship scientific
communicationskills.Contestantsare drawnfrom five learnedsocieties,includingthe
paper
published
leads
to
SG M.The finalistsare selectedby their respectivesocietieson the basisof posteror oral
The SGM Vacation
Studentshio
s c h e m eh a s
orovedvervsuccessfulin
g ivingundergraduatessome
e x p e r i e n c eo f w o r k i n gi n a
researchlaboratoryduring
t h e s u m m e rh o l i d a y sb e f o r e
t h e f i n a ly e a ro f t h e i rB S c .
ForSarahSmith,an awardee
presentationsand each receivesa S200 prize.Theythen go forwardto competefor the title of
Young Life Scientistof the Year Profilesof the two SG M contestants,Liz Mathew and Susan
McGrath,appearbelow
The l99BfinalsofthecompetitiontookplaceattheGeneticalSocietymeetingattheUniversity
of Warwickon 24 March 1999. The panelof iudgesincludedrepresentatives
from allof the
learnedsocietiesparticipating,
The i 0 comp-etitors
each madean oral presentationabouttheir
researchand Adele Marstonf romthe Universitvof Oxford,a f inalistf romthe GeneticalSocietv
was the winnerof a hard-foughtcontest.She receivedS2,OOO
and a glasstrophy.
in 1OQ7 it hac led tn
r t
r r
I r q v
r v v
! v
c o - a u t h o r s h iopf a s c i e n t iifc
o a o e r- a v a l u a b l ea d d i t i o n
to her CV.Sarah'ssupervisor,
D r R o b e r t J o n e so f t h e
Universityof Portsmouth,
reportsthat the paper,
e n t i t l e dA m i c r o b i o l o g i c a l
assayfor the sun protection
factorof sunscreen
p r o d u c t sw
l a s p u b l i s h e di n
J Pharm Pharmacol(1 998)
5 0 ( s u p p l e m e n t )p,. 1 3 8 ,
T h ep a p e rd e s c r i b e st h e
developmentof an assay
using Escherichia coli Io
measurethe orotection
factorof commercially
a v a i l a b lseu n s c r e e n
oroductsas an alternatrve
t o t h e c u r r e n t e s t sw h i c h
u s eh u m a nv o l u n t e e r st o
determinethe effectiveness
o f t h e c r e a m sa g a i n s t
ultravioletradiationf rom
t h es u n .l n d i c a t i o n fsr o m t h e
s t u d ya r ee n c o u r a g i n ga n d
a m i c r o b i o l o g i csayl s t e m
maywell providethe basis
for an animal-free testinq
syslem.
OContributions
for
gradline
fromyounger
are
SGMmembers
welcome,
I LizMathew
For me,furthereducation
l ollege,
b e g a na t l m p e r i aC
London,My interestin
m o l e c u l am
r i c r o b i o l o grye a l l y
developedaftercompletinga
vacationprojectin Deborah
Smith'sgroupon a myoD
!
homologue in Trichiietla
spirallis.I went on to do a
D P h i li n G e o f f r e yS m i t h ' s
groupat Oxford,which
involvedthe characterization
o f a v a c c i n i av i r u se n v e l o p e
protein,85R. As with most
other postgraduatedegrees,
minewas also'character
b u i l d i n g ' a nm
d y t i m ei n
Oxfordas a studentwas f un.
I am veryinterested
i n l e a r n i n ga b o u th o s t pathogenrnteractions
and I
a m e a g e r t oc o m p l e m e n t
m y e x p e r i e n c ei n m o l e c u l a r
virologywitha better
u n d e r s t a n d i nogf t h e i m m u n e
s y s t e m , l a mc u r r e n t l y
workingwith S,K.Alex Law
(MRClmmunochemistry
Unit,Departmentof
Biochemistry,
Oxford)on
l e u k o c y t ei n t e g rni s ,T h i s
positionis temporaryand has
providedme with an ideal
steppingstonefrom whichto
applyfor postdoctoral
positiona
s b r o a di n m o l e c u l a r
rmmunorogy,
e-mail
emathew@
molbiol.ox,ac
uk
w a s a t t h e l r i s hB r a n c h
meetingat UniversityCollege
D u b l i ni n S e p t e m b e r1 9 9 2 a t
w h i c hl w a s a w a r d e dt h e p r i z e
for best oralcommunication.
As a resultof this I was
nominatedto competefor a
PromegaPrizeatthe SGM
meetingat the Universityof
E a s tA n g l i ai n S e p t e m b e r
1998 where I was one of the
t w o w i n n e r sI.f e e l t h a ti t i s
extremelyimportantto
publicizeresearchand one of
t h e m o s ti m p o r t a nm
t ediums
f o r t h i si st h r o u g ha t t e n d i n g
conferencesand presenting
both in oraland poster
format.lt is alsoan important
meansof learningabout new
a n d u p c o m i n oa r e a so f
I Susan
McGrath
l g r a d u a t e dw i t ha B S c H o n s
i n B i o m e d i c aSl c i e n c e sf r o m
the Universityof Ulsterat
C o l e r a i n e ( U U C ) i1n9 9 5
a n d i t w a s d u r i n gm y
sandwichplacementyear
that my interestin research
b e g a nO
. n c o m p l e t i o no f m y
primarydegree,I decidedto
pursuea careerIn researcn
a n d b e g a nm y P h D s t u d i e s
u n d e rt h e s u p e r v i s i oonf
As padofthetraining
D r R ,H a y l o c ka n d D r J
I r e c e i v e dd u r i n gb o t h u n d e r Dooleyin the Biotechnology
and postgraduatestudies,
R e s e a r c hG r o u pa t U U C .
presentingwork and
My PhD studiesinvolvedthe
p a r t i c i p a t i nign J o u r n a C
l lubs
d e v e l o p m e n t oaf n R N A
was stronglyencouragedand
p r o v e dt o b e s u i t a b l et r a i n i n g assayfor Clostridium
botulinumtoxingene
for f inallypresentingdata
e x p r e s s i oa
n n dd u r i n gm y 3
f rom my own thesis.The
yearsI gainedinvaluable
opportunitytotalk at SGM
laboratoryexperiencein a
conferenceshas provideda
w i d er a n g eo f m o l e c u l a r
r e l a x e de n v i r o n m e nwt i t h i n
biologytechniques.I attended
my
w h i c ht o c o m m u n i c a t e
severalconferencesduring
data and exchangeideaswith
my PhD where I presented
o t h e rs c i e n t i s t sA. l s o ,w i n n i n g
my work in the form of poster
the Promegaprizefor best
a n do r a lc o m m u ni c a t i o n sM
.y
o p e n p a p e rw a s a n i c eb o n u s l
first contactwith the SG M
researchand vitalfor forming
collaborations.
At present,I am studyingthe
p o s sbi l ea p p li c a t i o n so f
competitiveRT/PC R for the
d e t e c t i o no f f o o d - b o r n e
pathogensand toxinsat
U UC, I hopeto extendmy
k n o w l e d g eo f m o l e c u l a r
detectionsystemswhich
m a yb e b e n e fi c i a l t ot h e f o o d
industrythrough f uture
postdoctorallearning and
i n du s t r i ael x p e r i e n c e .
e-mail
mcgrathsusan@hotmail
com
ffiffiffiPubllc
..
'::i..,;,,,.';'_
, , : ; 1 , ; . , , .,,: , , . . . ,
, , I , . , , r ' ; :; l ' ' ; , : I
Inthisissue,Going
on
Publicfocuses
someof SGM's
to
own activities
promotethe public
of
understanding
microbiology,
from
Contributions
readerson any
asoectof science
are
communication
alwayswelcome.
A s e t o f t w o p o s t e r so n t h e t h e m e o f e n v i r o n m e n t aml i c r o o r g a n i s m sh a s b e e n a d d e dt o t h e r a n g eo f S G M e d u c a t i o n a l
resources.
ll-
,*-***91+tT1
F - '
O NaturalWonderscoversthe amazingdiversityof microbial
h a b i t a t sm
, i c r o b i acl o m m u n i t i e sa n d t h e i r e s s e n t i a rl o l e i n
k e e p i n gt h e l i f ec y c l e so f t h e p l a n e t u r n r n g .
O W o n d e r fu l W o r k e r sg i v e s e x a m p l e so f t h e a p p l i c a t i o n s
d e v e l o p e db y b i o t e c h n o l o g i s tf so r m i c r o b e si n a g r i c u l t u r e ,
f o o d a n d p h a r m a c e u t i c aplr o d u c t i o np, o l l u t i o nc o n t r o la n d
bioremediation.
M o s t o f t h e i l l u s t r a t i o ncsa m ef r o m t w o S G M - f u n d e dp r o i e c t s
t o p r o d u c ea p o r t f o l i oo f m i c r o g r a p h so f m i c r o - o r g a n i s mast
d i f f e r e n tm a g n i fi c a t i o n sT. h e s ew e r e c a r r i e do u t b y s u m m e r
s t u d e n t sw h o h a v ep r o d u c e da n i n v a l u a b l ree s o u r c ef o r u s e i n
f u t u r ee d u c a t i o n apl o s t e r sa n d b o o k l e t s .
S i n g l es e t s o f p o s t e r sa r e f r e e f r o m t h e E x t e r n a lR e l a t i o n s
. o n t a c t J a n e W e s t w e l l f o r The last few daysof February
O f f i c e a t S G M H e a d q u a r t e r sC
l socgenm
icrobiol.org).
d e t a i l s( . w e s t w e l@
saw External Relations
O f f i c e s t a f { s p e n d i n gt i m e
in windswept and rainy
Glasgow al Careers 2000,
a n a t i o n a lc a r e e r s f a i r f o r
s c h o o l p u p i l s ,m a t u r e s t u -
sciencesW
. h e t h e rt h r s r s a
r e f l e c t i o no f t h e e d u c a t i o n
s y s t e mi n S c o t l a n dw e d o n o t
k n o w ,b u t i t w a s v e r y s a t i s f y ing to see so many young
p e o p l ew h o w e r e i n t e r e s t e d
in science, A significant
qaekinn
qnd
dontc
ncnnlp
n r r m h e ro f o r a d r r a t e sa l s o
^h^^^^ Trr
came to the stand seeking
d udr EUr ur rar 19E, | ilg s G M
o r o a n i z e d I h e R i o s c i e n c e s a d v i c eo n f i n d i n g w o r k i n
A c o m p e t i t i o np u t o n b y t h e
a t i l / o r k e x h i b i t i o n s t a n d t h e i r c h o s e nf i e l d .T h i s w a s
l n s t i t u t ef o r A n i m a l H e a l t h ,
i n c o l l a b o r a t i o nw i t h t h e l e s s e n c o r r r a o i n oh.u t t h e
C o m p t o n .a t t r a c t e d a g o o d
^^^^"^l
+A^*^
h^+
enerarT
Biochemical Society, the g
n e m e r+ n
ar came
r a n o e o f e n t r i e sf r o m c h i l B r i t i s hS o c i e t yf o r l m m u n o l - t h r o u g h w a s t h a t t h e i r
d r e n a g e d 8 - 1 4 . T h e yw e r e
o g y a n d t h e B r i t i s hP h a r m - d i f f i c u l t i e s w e r e p r o b a b l y
eclrad
ln
dacinn
a
nncter
annlnniral
Qnriairr
d r r et o n o o rC V n r e s e n t a t i o n .
i l l u s t r a t i n tgh e i m p o r t a n c eo f
L o u i s P a s t e u r ' sd i s c o v e r i e s J o h n S c h o l l a r f r o m t h e Biosciences at Work attends
a b o u t m i c r o - o r g a n i s masn d N a t i o n a lC e n t r ef o r B i o t e c h - )^ E^ ,V, E^ .t ^Att L d t E E t J +t A^ ii ,l -) U^ ^A^Lht I
n o l o g y E d u c a t i o np u t o n a y e a r a n d i s t h e o n l y s o u r c e
drsease.
' l i v e ' d e m o n s t r a t i o nw h i c h o f i m p a r t i a li n f o r m a t i o na t
T h e e n t r i e sw e r e j u d g e d i n
d
r o r r n so f f a s c i n a t e d t h e s e e v e n t s a b o u t h i g h e r
- , r" e 'w
' o
Y,
two aoe flrorns (8-1 1 and
o n l o o k e r sO
. n c et h e c r o w d s e d u c a t i o na n d c a r e e r si n t h e
12-14) by staff from the
s uture
w e r e h o o k e d , v o l u n t e e r s d i f f e r e n td i s r ^ i n l i n e F
Gl
I n s t i trrt e r e n r e s e n t a t i v eosI
'-' t"b
f
r
o
m
t
h
e
s
o
c
i
e
t
i
e
s
m
o
v
e
d
i
n
o
u
t
i
n
g
s
w
i
l
l
b
e
[
o
M
a
n
c
hesler
B B S R C ( o n e o f I A H ' sm a l o r
t' o- u
n i' v""e a d v i c e a n d i n f o r m - G N / l E X ,3 - 5 O c t o b e r ,a n d
cnnncnrc\
anrf
I iz Qnnlzatt
tr *- {* icr t q - t ,
' " ' /O
' ' l' v
t "m
' *n
' ia 13-14
ation about the different I nndon
$-t'"
t h e S G M E d u c a t i o nO f f i c e r .
b i o s c i e n c e sa n d c h o i c e s i n October.
T h e r e s u l t sw e r e a n n o u n c e d
h i g h e re d u c a t i o n .
tD Jane Westwell, SGM
i n S E T w e e ka n d t h e w i n n i n g
s c h o o l sw i l l r e c e i v et h e i r p r i z e so f S 3 5 0 f o r s c i e n c eb o o k s O v e r2 9 , 0 0 0 p e o p l ep a s s e d External Relations Offi ce
Rye a d(eBrB S R C ) a n d e q u r p m e n ta t t h e I A H ' s P a v i l i o na t t h e R o y a l S h o w , t h r o r r n ht h e d n n r s o f t h e
L i zS o c k eTt rt a c e
lVlarB
i oank e( pr r i m asrcyh otoela c h e r ) ,S t o n e l e i g hw, h e r et h e t o p e n t r i e sw i l la l s ob e o n d i s p l a y .
e x h i b i t i o nh a l l o v e r t h r e e
D a vCea v a n (al gAhH
& S c h oso'L i a i s o n
daysand a good proportion
Ceo l l i(el A
r Ha)n dB a r r y
0 f f i c eEr )l a i n
w e r e i n t e r e s t e di n b i o l o g i c a l
nn
g t r i ienst h e
F r e e m( laAnHj )u d g i e
P a s t epuors t ce or m p e t i t i o n
r1f
, ,
, v
L ,
L v
L v t
ffi
RR
IGHT:
UPPE
stand
at l4larkexhlbitlon
IheBioscienoe
2000,
Glasgow
aICareers
L O WR
E IRO H T :
c ri ro b i a l
C h i l d rdei snp l a y i n gm
t hi e
en
dh a n d k e r c hdiuerfisn,g
a r tp, a i n t o
FunDayseuenlal
IheFanily
Science
p 91
ng
ee
t h eU n i v e r o
s ifR
t ye a d i S
T h e w o r k s h o p s d e s c r i b e do p p o s i t e w e r e v e r y p o p u l a r
w i t h y o u n g c h i l d r e na n d w e h a v e s i n c e t a k e n s o m e o {
t h e a c t i v i t i e st o t h e E d i n b u r g hS c i e n c eF e s t i v a l .f t h e r e i s
e n o u g h i n t e r e s tf r o m r e a d e r sw h o a r e i n v o l v e di n p r o m o t i n g
m i c r o b i o l o gtyo s c h o o l st,h e n w e w i l l p r e p a r ew o r k s h e e t sf o r
t h e s e a c t i v i t i e sP. l e a s ec o n t a c t D a r i e lB u r d a s sf o r d e t a i l s
( d , b u r d a s s @ s o c g e incm
robiol.org.uk).
E'lrll{.:t{r:}.i:1!{i1'ir?ri;;?IoDAYVOL26/MAY99
nrt",f;f;r,
**Wfuw
W#wwffiffi
ffiffiffiwwrwffiww
ww#
ffiwwwwffi
ffiffiWffiffi&
1,".\"u'tq.l*t'**li.
[-]*r'i*i l**r';j;**l:'rr"bj***t ;i'-*r;r*t
,jmr:qj
T h e 1 9 9 9 N a t i o n aW
l eekof
Scicnr-e Technnlooy and
E n g i n e e r i n gw a s m a r k e d b y
the SG M on 20-21 March at
Ihe Family Science Fun Days,
U n i v e r s i t yo f R e a d i n g .A n
e x h i b i t i o nc a l l e d T h e S e c r e t
Worldof Microbesillustrated
t h e w i d e d i v e r s i t yo f m i c r o o r g a n i s m so n e a r t h a n d t h e
i m p a c tt h a t t h e y h a v eo n o u r
lives.
v v r v r
M o r e a m b i t i o u sa, n d u s u a l l y
older, visitors learned the
art of doinga Breedsmear
t o c a l c u l a t et h e n u m b e r o f
y e a s tc e l l si n a 5 l i t r ef e r m e n t a t i o n v e s s e l ,T h e p r i z e o f a
bottle of wine or mrcrobial
mouse-matoffered incentive
t o t h e s e i n t r e p i di n d i v i d u a l s .
r v v l
M i c r o s c o p e sb r o u g h tp r e v i o u s l y u n s e e np o n d l i f e i n t o
view and families were
fascinated by the diversity
o f s h a p e o f v a r i o u sa l g a e
and the sight of protozoa
z o o m i n ga r o u n ds l i d e si n f r o n t o f t h e i re y e s .
T h o u s a n d so f v i s i t o r sc a m e
+^ +t^ E,,^ tr\^.,^
ro rne FUn uays, rangrng
f r o m p r e - s c h o o cl h i l d r e nt o
grandparenls. The Secret World of Microbes catered for
a l l a g e g r o u p s w i t h e x t e n s i v ep o s t e r d i s p l a y sa n d s e v e r a l
P a s s e r s - b yw e r e a l s o i n v i t e d t o h a v e a g o a t t h e L u c k y
t y p e s o f h a n d s - o n a c t i v i t ya b l y s u p e r v i s e db y S G M s t a f f
Drp. Winners received a coaster depicting a range of
and volunteers.
m i c r o - o r g a n i s m sT. h a n k s a r e d u e t o S u p e r S n a p sf o r t h e i r
contributiontowardsthe cost of the coasters,
The SGM activities and
p o s t e r sw e r e c o mp l e m e n t e d
by display material on
comoostino from
the
H e n r y D o u b l e d a yR e s e a r c h
A s s o c i a t i o n ;p o s t e r s a b o u t
sewaoe treatment from
Thames Water; posters
illustratingthe water and
n i t r o n e n r - r r r - l e sf r o m t h e
BBSRC and NERC and a
small display on Ouorn
p r o v i d e db y M a r l o w F o o d s .
Staff from the Environment
P r e -a n d p r i m a r ys c h o o la g e d c h i l d r e ne n j o y e dm a k i n gs a l t - A g e n c yb r o u g h ta n e x h i b i t i o n
d o u g hm o d e l so r p a i n t i n gp r c t u r e so f e n v i r o n m e n t aml i c r o b e s a b o u t t h e i r w o r k a n d a l a r g e
o n c l o t h h a n d k e r c h r e f sg,u i d e d b y S G M ' s n e w E d u c a t i o n d i s h o f p o n dw a t e r c o n t a i n i n gg r u b sa n d b u g s f o r c h i l d r e nt o
Assistant,DarielBurdass.After a short introductronto several e x a m i n eS
. GM m e m b e rN i n aJ e n k i n sf r o m C A B I B i o s c i e n c e ,
m i c r o - o r g a n i s m sw h i c h a f f e c t t h e i r e v e r y d a y l i v e s , t h e S i l w o o dP a r k ,s e t u p a d i s p l a yo f p o s t e r s ,f u n g i a n d l o c u s t s
c h i l d r e nw e r e l e t l o o s eo n t h e s a l t - d o u g ha n d p e n s .C r e a t i v e . (dead and alive)to illustratethe LUBILOSA projectwhich has
j u i c e sf l o w e df r e e l ya n d s o m e b e a u t i f udl r a w i n g sa n d m o d e l s d e v e l o p e da m y c o i n s e c t i c i dfeo r u s e a g a r n s tl o c u s t sJ. o h n
r e s u l t e dH
. a n d k e r c h i e fa r t i s t st o o k t h e i r p i c t u r e sa w a y a n d G r a i n g e ra n d B o b R a s t a l l ,S G M m e m b e r sw h o a r e s t a f f a t
'best'
the
s a l t d o u g h m o d e lf r o m e a c h w o r k s h o pe a r n e dt h e R e a d i n gU n i v e r s i t yg, a v e u p t h e i r w e e k e n d t o s u p p o r l T h e
' c a m e r a m a no' n a v i d e o m i c r o s c o p e .
w i n n e rs o m e t i m e a s
Secret World of Microbes and staff from the National Centre
S e v e r acl h i l d r e nl e f t t h e e x h i b i t i o np r o u d l yc l u t c h i n ga v i d e o for BiotechnologyEducationalso contributedenormously.
c o n t a i n i n g3 0 - 4 5 m i n u t e sf o o t a g e o f f r e s h w a t e rp r o t o z o a
Our gratefulthanks are owed
an0argae.
to John Schollar,Kate Porter,
O t h e rv i s i t o r sl o o k e da t v a r i o u sb l u e c h e e s e su n d e rl e n s e s B e n e W a t m o r e a n d L a u r a
b e f o r es p e n d i n ga m e s s yh a l f h o u r i n o c u l a t i n tgo i l e tr o l l sw i t h P o u n t n e y ( N C B E ) ; J o h n
oystercap mushroomculture.They left with clear instructions G r a i n g e r a n d B o b R a s t a l l
( U n i v e r si t y o f R e a di n g ) ;
o n m u s h r o o mc a r e r i n o i n oi n t h e i re a r s !
Kathy Hurst and Gary
H o l m e s ;N i n a J e n k i n sa n d
-*
Jane Gunn (CABI Bios c i e n c e )a n d s t a f f f r o m t h e
EnvironmentAgency,
C Jane Westwell, Dariel
Burdass & Janet Hurst work
in the SGM External
RelationsOffice
s-,#**.
I H I SP A G E :
Scenes
atIheFanilyScience
FunDays
even
a tlI h eU n i v e r o
s ifR
t ye a d i n g
$}#$#ruffi
ffi$#e.{pffi'w
ToDAyvoL26lMAy
99 r
ffi
Agood
canbeeasily
found.
details
A classified
have
who
been
bookforthose
'brought
of
compendium
kits
and
forthose
up'on
andExercises
wholiketounderstand
alittlebit
bookreviewsfrom ByJ.Drtk$ra
&C.P.
deJager
works
about
howatechnique
GmbHmore
bySpringer-Verlag
1996 to the present Published
it.
ratherthan
simply
use
KG
&co.
0998)
'l
onthe
isavailable
.00AFrl
35.00/ lBobDalziel
DM 48.00/t
51081
University of Edinburgh
pp.
SGM website,
459
US$99.00,
S57.00/
production,
tomore
comprehensive
hybridoma
reference access
Thisvolume
toamore
specialisttextwould textsmayberequired,
probably
recommended
asabasic
benecessary
ifthereader ishighly
reference
textforalltissue
culture
inthe
wasinitiating
thetechnique
laboratories,
laboratory,
Asthechapters
are
lAndySpencer
organized
under
specif
ic
rather
thangeneral Veterinary Laboratory
applications,
Agency,Addlestone
techniques,
there
isrepetition
of
some
methodology,
forexample
ISBN:3-540-63759-1
'Western'
Forthereader
blotting.
Afipia
)nartoneltaand
lUtolecular Uariability whohasexperience
ofthese
manualis
aimed
This
laboratory
Vof FungalPathogens
techniques
thisgives
aninterestingVSpecies Emphasizing
ofnlant
atstudents
andteachers
Bartonella henselae.
Y.Couteaudier
Edited
byP,D,
Bridge,
in
insight
intothevariety
ofways
virology,
andalso
atresearch
to
Gontributions
which
laboratories
different
lt provides &J,Clarkson
andtechnicians.
workers
Microbiology,Uol.1
International successf
byCAB
guide
the
ullyreach
essentially
toclassical Published
acomprehensive
byA,Schmidt
I have
same
end-point.
oneminor Edited
methods
ofhandling (1ss8)
andmodern
byS,KargerAG,
Basel
pp,336
quibble
plant
inthatFreund's
complete Published
viruses: S55.00/US$100,00,
andcharacterizing
es8)
(FCA)
isdescribed
inone (1
adjuvant
has ISBN:0-85'199-266-8
avowed
intention
theauthors'
27.00.
cHFl46,00/DM175.00/
US$1
chapter
ascontaining'heat-killed
tried
andtested
been
tostickwith
pp,218
The
fungi
aremutable
beasts,
pertussis
rather
than
bacteria'
andavoid
themost
nrocedures
exhibiting
variability. MycobacteriumtubercuIosis.Also ISBN:3-8055-6649-2
continually
Thegreat
recent
developments.
when
using thedangers
canbeannoying
ofFCA
fortheuserif a
inthebook This
ofthematerial
majority
book
isthefirstinthe
butis
asexperimentaltools,
needle*tick
injury
occuned
should This
theexperiencedthem
willbefamiliarto
Contributions toMiuobiohgy
partoftheir
This
nature.
clearly
plantvirologist:
have
highlighted,
This
book
been
isin
itsmerit
series,
lt consists
of14chaoters
isanassemblage
of19
book
willbe
both
those
who
usefulto
awiderange
of
bringing
such
panel,
written
byaninternational
ofvarious
separate
accounts
have
in
already
some
experience
In
inoneplace,
methods
together
giving
anoverview
ofinfection
variability,
lt is
aspects
offungal
probably
protocols
in
thisarea
and,
andsubsum,89
byBarlonella
andAfipiaspp.
ofanECworkshop conjunction
protocols,
withother
methods caused
ranging
frominfectivity theoutcome
isclear,
withtables
not
anddoes
whowishtoembark Thelayout
texts,
tothose
aredescribed;
there inSeptember'1997,
assay
toPCR,
anddiagrams
thatareeasy
to
give
acomprehensiveonnewtechniques.
attemptto
The
exercises.
are17practical
understand,
andthetextiswell
lt covers
a
review
ofthesubject,
lsheila Patrick
are
ofthemethods
descriptions
written.
Thesections
plant, The Q,ueen'sUn iversity
concerning
wide
range
offungi,
mostly
with
very
andthorough,
detailed
laboratory
methods,
including
pathogens.
invertebrate
andhuman
of Belfast
information
onhow
background
molecular
techniques,
are
pathogens
getmost
Theinsect
Most
sections
are
work.
things
particularly
Thechapters
useful.
devoted
withsixchapters
diagrams. coverage,
illustrated
withhelpful
independently,
aseach
canberead
lAnimal
GellGulture
chieflytoMetarhiziumand
aid
Recommended
asateaching
However,
covers
adiscrete
subject.
VTechniques
forexample,
Beauvaria,one,
on
embarking
andforlaboratories
irritation
isthatthere
is
aminor
Edited
byM,0lynes
variability
duetothe
plant
virus
studies,
butattheprice, describing
repetition
between
bySpringer-Verlag
GmbH considerable
Beauvaria- Published
Resf/esstransp
osonin
perhaps
beyond
themeans
them.
Several
comprehensive
There
isalso
a &Co,KG(1998)
related
fungal
stains.
student,
oftheindividual
reviews
olBaftonellainfections
viruses, DM188.00/6S1,373.004Frl70.00/
brief
accounl
offungal
f Ron Fraser
pp.618
have
appeared
recently
inmajor
S72,50/
US$119.00,
bybeing
areunusual
SGM Marlborough Hous€ which
journals,
including
of
twobysome
3-540-63008-2
transmitted
only
byintracellular ISBN:
thecost
thechapter
authors.
Given
routes.
Inconclusion,
thisisapotprovides
ofthisbook
andthefactthatthis
insight
intoa
book
pourri
accounts, This
ofwellwritten
lMolecular
progress
rapidly,
I
ofanimal
cellculture fieldislikelyto
most
mycologists widerange
among
which
UBiomethods
particularly
wonderwho
willneed
tobuyit.lt
those
ofinterest, techniques,
should
findsomething
Handbook
forinstitution
bevaluable
associated
withbiochemistry. would
Edited
byR,Rapley
&J,M,Walker lGrahamGooday
andperhaps
larger
methods,
Cell libraries,
Sections
onGeneral
(1998) Universityof Aherdeen
Press
Published
byHumana
proliferation
departments,
butnotforthe
Models
of
anddeath,
pp.704
US$89.50,
-8
individual,
whocangetthesame
celldifferentiation
andModels
ISB
N:0-89603-501
journals,
llmmunochemical
fromreview
are information
oftoxicology
andpharmacology
lNickBrown
Each
lays
included.
chapter
out
probably
more VProtocols, Second
and,
I liked
thisbook
precise,
procedures
giving
step-by-Ad de nb roo ke's H ospital,
importantly,
sodidmyPhDstudent. Edition.Methodsin
which
areeasy
to Cambridge
covers
0neparticularMolecularBiology,Uol.80 stepinstructions
Each
chapter
Edited
byJ.D,
Pound
readandcarryout,Thebackground
HPLC,
RFLB
technique
e.g,
('1998) information
Press
byHumana
foreach
topicis
vary Published
Thechapters
Southern
blots.
Engineering:
tJs$69.50
detailed,
up-to-date
andaccurate, lGenetic
butallgive
a
intheir
approach
VPrinciplesand
ISBN:
0-89603-388-0
particularly
The
is
suitable
for
book
of
overview
of
the
basis
reasonable
researchers
whoarerelatively
new Methods,Uol.20
gointoa
andsome
thetechniques
Edited
byJ.K.Setlow
protocols
provides
ofa
tothepractice
ofcellandtissue
include
some Thisbook
little
more
detailand
Published
byPlenum
Publishing
methods culture,
ofimmunochemical
providing
asound
it if range
notrecommend
recipes.lwould
(1998)
Corporation
interestto
which
are
likelyto
be
of
introduction
many
of
the
modern
to
youwanted
howto
know
exactly
to
pp,292
US$95,00,
lt isatreasury applications
biologists,
inresearch
and
butif molecular
forexample,
aYAC,
construct,
ISBN:
0-306-4591'l-6
information,
bothwithin development.
ofdetailed
However,
assuch
a
youwanttoknow
therationale
andintheNotes
theprotocols
iscovered,
wide
range
oftopics
the
it'sagood
thetechnique,
behind
inthisseries
was
insome
which
chapters depthofinformation
sections,
provided
is,in Thefirstvolume
are
on
the
resource.
Thechapters
in1979,
neweditions
However,
forsome
of some
areextensive.
Insuch
cases,
limited.
cases published
andso
whole
wellreferenced
year
In
appearing
each
since
then.
as
covered,
such
thetechniques
ofi"liffilll3fJ,,,,
g
6*tu$}#vropAY vo L26l MAY99
ffi $*$aqpffi
years
theearly
theseries
hadan
volume
isthemost
comprehensive
Function, excellent
and
stimulating
lorun oamage
lSpecificity,
perceived
easily
identity,
since
reviewto
Uol.2:
dateofthemethodology Vand Deuelopmentof introduction
Vand Repair,
byRobin
Weiss,
which
therewererelatively
fewprinciples DNARepair
in Higher
associated
withsynthetic
and
NKGells.
NKGells:
The
conveys
both
anaccurate
sense
of
andmethods
todescribe,
Genetic Eukaryotes.
Gontemporaryendogenously
expressed
ribozymesEffectorArmof Innate
history
and
real
excitement
of
engineering
isnowused
insuch
Gancer
Research
a
incellculture
andanimal
models, lmmuni$. GurrentTopics thingsto
come
inthehuman
pertaining
widevariety
ofsituations,
however, Edited
byJ.A,
Nickoloff
Details
&
toribozyme
in Microbiologyand
tumour
virus
field.
Inthefinal
purification
thatit isinevitable
thataseries
M.F,
Hoekstra
synthesis,
and
lmmunology,
Uol.230
chapter,
most
oftheauthors
ofthe
(1998) biological
which
attempts
tocoverthe
whole Published
byHumana
Press
activity
testing
Edited
are
byK.Kiine& M,Colonna other
chapters
combine
forces
to
pp.
subject
willlose
focus.
25,00,
US$l
672
included
forthe
most
commonly Published
bySpringer-Verlag
GmbH provide
agood
overview
ofthe
Consequently,
(Hammerhead,
thisedition
includes ISBN:
0-89603-500-X
studied
ribozymes
prospects
&Co.KG(1998)
forvaccination
and
chapters
specific
tomammalian,
Hairpin,
Hepatitis
Delta
Virus
DM224,00/t'S1,636,00/sFr202,00/
and
therapy
ofvirally
mediated
human
plant
andamoebic
systems,
The
second
volume
inthisambitiousRNaseP)
pp,248
foradiverse
range
of
S86.00/
US$1
49.00,
cancer,
Asmall
reservation
isthat
-1
together
withmoregeneric
in vitro pair
covers
higher
eukaryotes, applications,
including
thetargeting ISBN:
3-540-63941
byfocusing
onhuman
tumour
andcomputer
methods,
which
This
turn
outto
bemammals, ofviruses
such
asHlV,
hepatitis
B
viruses
bygroup,
andnotgiving
isminored
diversity
bytherange
thenematode
of Plants,
C.elegans, andinfluenza,
andcancers
ofthe
This
isatimely
book
collection
much
of
detailon
non-human
tumour
'1.
pancreas
approaches
taken
andfrogs
were
bythe
inVol, The
articles breast,
andlung.
I
(e,g.
excellent
polyoma)
articles
onnatural
killer viruses
SV40,
and
give aresummaries
contributors,
Some
chapters
either
ofdifferent thoroughly
recommend
thisvolume (NK)cellactivation,
receptor
human
viruses
thatcause
tumours
pathways,
superficial
overviews,
whilst
others repair
setsofenzymes, toallnewcomers
andestablished interaction
(e,9,
anddevelopment.
Lysis inanimals
adenoviruses),
some
gointogreatdetailandtheyrange oranalytical
methods.
Authors
are groupsworking
withribozymes,
A
oftarget
cells
andsecretion
of
veryinteresting
common
evolved
inlength
from8to48pages,
The
acknowledged
inthefield good
experts
companion
tohave
byyour
cytokines
byNKcells
iscontrolled mechanisms
intumorigenesis
are
complete
series
mayprovide
a
andtheresult
isarticles
ofgenerallysideonthelabbench!
bydistinct
combinations
of
lost
from
consideration
here,
quality,
useful
resource
inalibrary,
lSaghirAkhtar
butitis very
high
inhibitory
point
andactivation
receptors. However,
thisisasmall
Aston University
unlikely
thatthissingle
edition
[)verviews
oftranscriptional
and
Since
thelatter
remain
mostly
balanced
againstwhat
isahighly
post-translational
would
bemissed
frommost
responses
to
elusive,
many
ofthechapters
deal recommended
book,
personal
genotoxic
pull
bookshelves.
stress
together
a
withthereceptors
f EricBlair
andco-receptors
lGlenn Matthews
life
luirus
in
huge
amount
ofdata.
There
is
involved
ininhibitory
function,
The UniversityofLeeds
Queen Elizabeth
overlap
between
afewchapters, VDiagrams
roleofNKcellsinthelysisoftumour
ByH.-W
Hospital, Birmingham
Ackermann,
L,Berthiaume
butinmany
cases
thispresentation
andvirally
infected
cells
isalso
dealt
ofdifferent
viewpoints
works
tothe &M.Tremblay
withunder
anumber
ofheadings, lAdenovirus Methods
Published
by
CRC
Press/SpringerVand Protocols.
reade/s
advantage.
There
are
However,
NKcells
also
f unction
Regulation.
(1998)
GmbH
&Co,
KG
lCene
in Molecular
exhaustive
reference
lists,
though Verlag
bysecreting
cytokines,
especially Methods
VAEukaryotic
45,00/t
S1059,004Frl
32,00/ IFN-y,whichhasanimportant
Uol.2l
notevery
chapter
hasclearfiguresDM1
role Medicine,
Perspectiue.Third Edition and
pp,221
$56,00/
U5$69.95,
byWS.M.Wdd
tables,
Ingeneral
there
isan
ininnate
defence
early
ininfection Edited
ByD.S.
Latchman
ISBN:
0-8493-31
26-9
(1998)
(asof
Published
byHumana
Press
excellent
and
up-to-date
andcanselectively
enhance
the
Published
byStanley
Thornes
pp.704
early
1998)
scope
ofcoverage
that
type1armoftheadaptive
immune US$99,50,
(Publishers)
Ltd0998)
isacollection
ofpreviously response.
ISBN:0-89603-551-4
willbeuseful
toactive
researchersThis
From
themicrobiologist's
pp,329
S24,99,
diagrams.
Asaresult pointofview,
inDNArepair,
students
perhaps
exploring
a published
one
ISBN:
0-7487-3977-7
each
diagram
isdrawn
inadifferentweakness
particular
The
use
ofadenoviruses
asgene
area,
oroutsiders
ofthebookwas
the
andforeach
virus
avarying scarcity
guarantees
delivery
systems
wanting
a
anoverview
ofasubject. style
ofinformation
onthe
This
isanimproved
edition
ofan
amount
ofinformation
isgiven.
lRickWood
strong
interest
bymany
research
function
ofNKcellsinimmunity
to
already
useful
basic
text,lt hasbeen ImperialCancer
There
has
been
noattempt
to
protocols
laboratories
ingood
for
infectious
diseases:
less
thana
brought
up-to-date
andextended, ResearchFund,Clare
theformat
ofeach
t standardize
ofadenovirus
mutants
pageoftextisdevoted
totheroleof construction
thus
offering
more
tothereader, Hall Laboratories
entry
such
thatallaspects
ofthelife NKcellsinanti-bacterial
recombinants
and
their
use.
immunity, and
Part
oftherevision
hasbeen
the
cycle
arecovered,
There
hasalso lKingston Mills
quite
This
book
caters
wellforthose
inclusion
ofmore
basic
materialon
been
noapparent
attempt
toedit National Universityof
grow
who
simplywantto
prttcess,
thegene
expression
thematerialand
many
diagrams lreland, Maynooth
adenoviruses,
assay
them
anduse
pleasing
However,
it isparticularly
processes
cover
thesame
asthose
protocols
them,
The
arewritten
ina
Riborymes.
Methods
in
tosee
theadditional
sections
on
pages,
onadjacent
forexample
standard,
detailed
way
ineach
post-transcriptional
Medicine,Uol.
11 there
control,
These Molecular
areseven
different
diagrams lUirusesand Human chapter
and
seem
easy
towork
Edited
byK.J,
Scanlon
may
besomewhat
limited
in
outlining
thepoxvirus
vGancel
lifecycle
from.
More
advanced
topics
are
(1998) fromentryto
Published
byHumana
Press
coverage
incomparison
tothe
Edited
byJ,R,Arrand
maturation.
&D,R.
Harper included,
This
is
such
asgrowth
of
pp,480
US$
99,50,
considerably
more
extensive
yetthere Published
repeated
formany
byBl0S
viruses,
Scientific fastidious
adenoviruses,
thestudy
ISBN:0-89603-477-1 is,forexample
treatment
oftranscription,
butdo
Ltd(1998)
nodiagram
outliningPublishers
oftheimmune
response
to
make
thisbook
more
balanced,
pp.200
thereplication
S35,00,
cycle
ofthe
adenoviruses
and
molecular
and
-872748-44-9
areaclass
ofribonucleic
0verall,
thisbook
isawellwritten Ribozymes
parvoviruses,
ISBN:
1
autonomous
Iam
cellbiological
methods
forstudy
of
possess
provides
acid
that
enzymatic unsure
and
lucid
workthat
a
atwhom
thisbook
isaimed:
infection
andcelltransformation.
can
beused
sound
introduction
to
tothisimportant propertieswhich
perhaps
isanexcellent
lwould
useitasateachingThis
introduction
to ()verall,
thisisaverycomprehensive
gene
inhibit
expression
inahighly resource;
field
foradvanced
undergraduates,
tumour
virology,
however,
ifyouareonly human
suitable
for methods
book
thatwillbea
po$graduates
sequence-specific
manner
by
andresearch
interested
inasingle
undergraduates, laboratory
virus,
Fields advanced
years
standard
forsome
g
lysin thetrans-cleau
scientists
whoarenotspecialists
age
of
in cata
postgraduates
isprobably
and
abetter
research
bet,
tocome.
priced
target
RNA.
Assuch
these
thefield,
This
reasonably
lBobDalziel
workers
entering
thefield.
Aswell f EricBlair
(a.k,a.
paperbackwill
RNA
enzymes) Unive rsityof Edi nburgh
beaworthwhile molecules
group
astreating
UniversityofLeeds
each
major
of
purchase
been
increasingly
used
as
formany
suchindividuals,have
human
tumour
viruses
in
gene
tools
tounderstand
butgiven
therapidpaceofadvances biological
(hepatitis
reasonable
detail
viruses,
asdrug-target
inresearch
ongene
expression,
the expression,
papillomaviruses,
Epstein-Barr
validation
agents
and,
thefocus
author
maybeinvited
of
toprepare
a
viruses,
Kaposi's
sarcoma,
human
thisvolume,
aspotential
fourth
edition
verystlon,
herpesvirus
I andoncoretroviruses),
llohnMcCarthy
therapeutic
agents,
This
timely
thebook
isenhanced
byan
UMIST,Manchester
olffitflttit'i,t,,
ffiffi
#ffiffi{sffi*#tuffi#yloDAyvol26/MAy99 E
Readers'reactions to the articles on GM crops and food in
the February issue of MicrobiologyToday
effects?
Whataboutthepositional
Dear
Editor
I greatly appreciatedthe four articleson geneticengineeringof
plants, for their content and the courageofthe viewsexpressed.
However,I wassurprisedthat no mention wasmadeofposition
effects,describedabundantly in geneticstextbooks,at least
thoseofa generationago.The random insertionofa genetic
elementinto agenomeby non-homologousrecombinationis
from the
likely to affectthe information presentand expressed
region ofinsertion, giving riseto unpredictableside-effects
separatefrom the functionality ofthe insertedsequence.
Insertionsmight affectnot only growth pattern and
morphology,but alsometabolicequilibrium which
would be lessobviousand more difficult to detect.
The textbooksmention examplesofpositional effects
and transposableelementsfrom animalsranging from
bi la tohumans,and BarbaraMcClintock'spioneering
Drosop
studieswith maizearcjustly famous.Later studieswith
haploid micro-organisms,suchasthoseof\WernerArber,
establishedthe importanceof insertionsand inversionsin
causingspontaneousmutations, especiallyinsertionsinto
In the first issue,PeterCotgreaverightly beratessloppy
writing about microbes.Nfe must be just ascarefulto avoid it
when venturing into non-microbiologicalcontexts.
Among the interesting articleson GM foodsand crops,your
editorial obserues:"Vhat is undoubtedllmotiuatingtbe
at presentisprofit and theneationand
companies
biotecbnology
expansion
of marketsbare". " At present",you write: areyou
biotechnology
expectingchange?Like all businesses,
companiesarealwayslooking for profit. A companyis not a
charity; if it neverexpectsto beprofitable, therewill be no
investmentand no company,biotechnologicalor otherwise.
One of the complaintssometimeslevelledat the scientific
community is its unfamiliarity with the realitiesofbusiness
and economics.Surelythat cannotinclude the Editor of
MicrobiologyToday.
\Wirh fraternalgreetings.
O Professor VivianMoses
Division of LifeSciences, King's College London
plasmidsand bacteriophages.
\With plants, the increasingavailability of sequence
information may make it possibleto target the transgeneto
to
specificregionsofthe genome,by adding host sequences
eachend in an attempt to achieveinsertionby homologous
recombination.But this, and the continued needfor screening
will be time-consumingand counter
forpositional side-effects,
to industrial pressuresfor commerciallyusableproductsthat
Gonference
give profits within a short timescale.
tO Professor Emeritus Eduard Kellenberger
IGBM de l'Universite de Lausanne, Switzeiland
G enet icalljt Modified F oods
& lngredients: tbe uay
fonuard
22-23June 1999
Royal MarsdenHospital
NHSTrust, London
ContactIBC Global
Ltd
Conferences
TeI.0171
4t31496
information
Fuilher
The featurearticles on GM plants and foodin Mirobiology
Todaycoincidedwith a huge amount ofmedia interest in the
topic. Public concernhasbeensuchthat many supermarkets
and food companieshavenow banned GM ingredients from
their products.Inquiries into aspectsofthe subjecthavealso
beensetin motion by the UK governmentand bodiessuchas
the Royal Society.As a result ofall this interestseveraluseful
leafletshavebeenproducedby the researchcouncils.
G M0 s and tlte Enuironment: scientific certaintiesand
uncertainties
AG page A4briefing note from NERC which examinesthe
the risks
with geneticmodification and assesses
factsassociated
for the natural environment. Available from: NERC Planning
& CommunicationsDirectorate,PolarisHouse,North Star
Avenue,SwindonSN 2 IEU (e-mail [email protected]).
.I nG EN E i ous: t b esci enceand issuesof genetic ntodifi cati on
A DL size,Bpageleaflet from the BBSRC coversthe background
to the topic, the debate,issuesand concerns,GM and animals,
GM and crops,applications and a useful reading list. Available
from Public Afiairs Branch,BBSRC,North StarAvenue,
Swindon,SN 2 ITJH(e-mail [email protected]).
ffiffiw
cl
T
ftrr
HelOcHEM[Af
EBI0CH
E M l\/rn[lc
I C A L S 0HCUI E
GP A T H
s0cmv
MTAYNMFE
UENTGI N
AL
ENST
l;lIi a
i lf,i ri-1;-"1"i
ilil
;i'0 Giilll",#3'flir
L{
t{ ;: ';t'* #
FUNGAL
DIM0RPI-|ISI/I
AND
DISEASE. r " . . " r . : i . , rl lj #
If Yj
ij
ilj
universitv
Keere
Universitv
ofKeele
ffi
PROIEIN
TARGETING:
MECHANIS[lIS
to-zziliyidbe
Granada,spain
CYAN0BACTERIA:[/lECHANISMS_0F_..
AND
CO[/1PONENTS
OF
PROTEIN
4-gSepiembel
lggg
nn,r^nr,rr^'.
n,r^^ri"^"
n++i".
t
uNrAU|:
In€r\/reerngsuilrce
ENERGyC0NVERSI0NANDELECTR0N
TO
SORTING
SUBSELLULAR
Biochemical
Porfland
Place
Society
59
C0NTACT:
J
Hendekovn
Euro,pean
TRANSFER
COMPART[/lENTS
0171
580
3481;
(Iel0171
London
W1N
3AJ
5803481;
Austria
Austria
Gmunden,
Gmunden,
0bernai,
nrStrasboulg,
France
i:lt1l|JJt%l,0'
i::'#:'|iil?flX'#,118]fl1[t[iTl,,
Fax
0171
637
7626;
1999
5-10June1999
5-10
June
1-60ctober
1999
e-mailmeetings@biochemsocorguk;
Lezay'liarnesia
e-mail
meetings@biochemsoc
orguk;
6T080StrasbourgCedex
(Fax
+333BB
France
biochemsoc
org
uk)
366987;
European http://www
J Hendekovic
Euronean
C6NTACT:
C0NTACT:
C0NTACT:
J.Hendekovic
European
emaileuresco@esf
org:
European
ScienceFoundation
0fficeof
Science
Foundatron
0ffice
ofEuropean
r r. &
http:/iwww
esi
o's/euresco)
(EURSSCO|
(EURESC0)
Research
t quar 5: I i I I i i \. i ji:
Conferences
Research
Conferences
1quai
Lezay-Marnesta670B0StrasbourgCedexq;\'tjq'Ji.|Y*.ffi
Lezay-[/arnesia
67080
Strasbourg
Cedex
(Fax
+33
F r a n c e ( F a x + 3 3 3 8 8 3 6 6 9+8S
/ :T | ] H A R I f N C 0 N F F R F N n F
France
3BB
366987;
University
C.ollege
c-ork
e-maiteuresco@es{ors;
FUNCTI3NAL
Aspiirs'bii1trne1,
7-eSeptember
1999
g'RArNiRriAiiolsHlp
http://www
esi6rs/euresco) [/lETABILlslll
rrrr
: ,t -. *
i; I" a
! :| ;J i:i1
'
.ti J f'
XilI\ITERNAI3NAL
\V1R,$mp/
RAPID
METH0DS
AND
syftllpOsltJM
AUT0[/AT|0N
lN[/|CR0B|0L00Y
o
o rur r' u
o cununu6voucu{ i ,nur ,n
v -, m
, , roi l, ,u
I,
http
://www
e$org/euresco)
T0BRAIN
DEVEL0PMENTAND
C0NTACT:The[/eetings0ffice
l
.,
"r ,.
.l
NEUR0DEGENERATIVE
DISEASE Biochemicalsociety
59Porrrand
Prace
0171
580
3481:
Evnsham
Ha1.
North
!tt{*I]},4J"(Tel
rrrLeioh.
--rrr'
Fax
ul/lb3//b2b:
SECOND
FOCUS
ONFLUORESCENCE
;i'dffi
e-maitmeetinss@biochemsoc
orsuk;
SYMPOSIUM:
EXCITING
DYES
AND
ii_i'iiirinustrgss
'- - hrlp://www
biochemsoc
orsuk)
THEIR
APPLICATIONS
":, :-:::--'
Leiden,
TheNetherlands
1999
(iet0171
London
WlN
3AJ
580
3481: [[!'jBiflt|^K^i,YA,n5l'"u 26-27November
" ;":'": .:,l:j
THE
NEW
[/ILLENNIIJM
SHAPING
3fliI|IHT#ffiI]T3BIlfrI,.O
,',,, YPTFIIIRIB]PIS9I^SITIIA
Kansas
State
University,
USA
e-16July
leee
Fax
0i71
637
7626;
C0NTACT:
[/slrme
vanderHeijden,
iiia'iliA'$illtinruftFbnr
'
org
uk'
C0NTACT:Janice
Nikkel
Conference email,meetingsPbiochemsoc
I
[/olecular
Probes
Europe
Poortgebouw
http://wwwbiochemsocorguk)
Castelvecchio.Pasc_oli,ltaly
+178bb32254i]:
Rijnsburgerweg
Coordinator(Tel
10,2333
AALeiden
I
I
I
U
u
E
P
r
E
I
I
r
u
E
r
r
u
u
i
'
11-16September1999
/ w*",ij^,s
ww
(Tel
+31715233378;
e - m aj ni l i k k e l @ d c e , k s u , e d u : h t t p
e-mailjnikkel@dce,ksu,edu;http:llwww,
The
Netherlands
F,.: ./d{
. _***, IL*,&,
b . s.,
. " t'li
a \,$q
".t
d c e k s u e d u i d c e /c o n f/m5iIlc ro
Fax+31
715233419;
J HC
endekovi
T E uropean
c
lbi
:-.^
i ol
l i 'osy/)
,r i l ;f " + ' ; O0N TA
e-mail
eurotech@probes
nl)
0fficeof
European
NMR-lNM0IECUtARBIOLO6I
.".^:f.
._;._.^^^:" " SctenceFoundation
quar t l
MICR0BIALAQUATICSYMBI0SIS.
ResearchConferences(EURESC0),1
sTRlcTlRF
RtNntNnANn
"
PRESENTED
BY
THE
J0INT
AQUATICLezay-l/arnesia,67080
Strasbcurs
Cedex" j i " , -. "" '",;,;' .I.:"; ' . 1: ; " . " \
RiabcftiigN
x710tigi1iA.p
(Fax
ASS0CIATIONS
0FTHE
UK
fdlffiSliils'JL
France+33
3BB
366987:
e-maiieuresco@esf
ors:
ADVAI\ICED
COURSE
ON[/ICROBIAL
for
" Marine
lq{,t! Association
PHYSIOLOGY
ANDFER[/
ENTATION
IECH
''NTACT:JHendekovcEurolean
NOLOGY
fl'$tri'11iil;;;; ffi
pHySI0L0Gy0FF00DRELATED
0fficeofEurcpean
scienceFoundation
nnn,rnnr,n,n^,,^r^"r\r^r^.,i^
c^^+i"h
DelftUniversity
olTechnology,
(EURESC0)
Research
1quai ii"l jll^ll^YiiY,1'^'l:l'll'l'"i::"''"MICR0
Conferences
0RGANISMS
THE
17TH
The
Netherlands
|
nrrur;rdtrur
'''
'to'
'l'l
n'd'"
ou"
Lezay-Marnesia
67080
Strasb
'
0SIU17l
0FIHEINTE
RNATI0
NAL 6-17December
.o:ftlluj ::oll,
1999
(Iel01631
"", SYx4P
bb/832;
faxulbsl
(Fax
+833BB
f4344tD
France
366987;
inn,rrurnrr
0NF00D
MtcR0Bl0L0Gy
571150:e-maildmck@dmlac
uk;
e-maileuresco@esf
org:
DrlrLAvanderMeer-Lerk
C0NTACT:
(lCF[/H)
lfrfii IYGIENE
'"""
, http://wwwnerc-obanacuk/dmll
http://wwwesfrrg/euiesco)
In$itute
forBiotechnology
Delft
Studies
(B0DL)
Leiden
Kluyver
Laboratory
Julianalaan
672628
BC
Delft
The
irurnnfiruil\rtrur\rrtrt|\rtrt,
ACTIVITY
EC0L0GYAND
(Tel
+31152181922',
ANNEXINS
C0NTACT,
ICFMH
Congress
Servrce Netherlands
AppLtCntnruS
+31152182355,e-mallbodl@$m
Fax
(Fax
+31
Brabant
The
Nethedands
40
Wye
College.,
rryl^^
Granada,
Spain
tudelft
nl;http://www
kluyver
$mtudelft
nl/B0DL/ACS
htm)
r!
c0NTACT:The[/eetingsOffice
DrJose-[/inrrcr
c0NTACT:secrerariat
^
DIFr
GUTFUNCTI0NANDHEALTH ' " * . i : " \
i' ,i!*
B a r e a C o n s e j o S u p e r i o r dBei'os cuhue' m t c a l s o c i e t y 5 g P o
: lr' t l a n d P l a c e
*. ".'L'"r
(Tel
W'lN
3AJ
0171
580
3481; TheRoyal
Society
ol Medicine , t : ; ;
tnvpsrinrninnps
tipnrifinrs
Fsrrninn London
-"'*'ar'r,,,0,.t,
""i
Fax
0171
637
7626:
london
gE Y ON
IT N OIT
Experimental
del
laidin
Profesor
TUGE
meetings@biochemsoc
org
uk,
z?-zlSeptember
1999
1 lgnng
firrnrr]r
Snain
rror*:+ in ii" e-mail
1BTH
INTERNATIONAL
CONG
RESS
http://www
biochemsoc
orsuk)
i0iii;* .34ttill gooo,
BIOCHEMISTRY
AND
MOLECULAR
00NTACT:
Emma
Brvce
The
Rovat
socretvOF
[email protected],es:
fUtrtlnttrtf
HttnLnSPECIS
0FSURFACE
oIMedrcrne
1WrmnoleStreet
London BIOLOGY
j 290
edu/grenada/) sclINCE:
http://www
css
orst
RE
AN
DDYNAMICS
STRUCTU
wlMBAE
3919;
0et017
International
Conference
p.lqBlAN]Q
AIID
BI0L0GICAL Fax01112e029,77',
F,t I/JRIND0RFSE^SSCITy
F3R
'
Centre,
Birmingham
[/I0LECULES
AT
INIERFACES
e-mail:events@roysocmed
ac
uk)
npFLif
nMtlnOetOLOefSU[/MlR"
16-20July2000
C0NFERENCE
Pascoli,
ltaly
Castelvecchio
C0NTACT;
Andrea
Buxton
Centre
1999
3-8September
ofYork
Exhibitions
University
The
NEC
Birmingham
840
14-16Ju|y1999
1NT(Tel
012176/3755;
Fax0121
16l
C3NTACT:J.Hendekovic
European
genome@necgroup
3535
couk)
;e-mail
Science
Fou
ndati
on,
European
0ffrce
DrAn
nBai
llie,
Society
for
_of
C0NTACT:
Corferencel{lURESC0)
1quai
iheBloreiowe, Research
Applied
[/icrobiology
ly3tnesnr6T-0pQ
Cedex,
The
Harpur
Centre
1jedford
MKag
1iq
itlqsbrurg
fezav
(Fax
+333BB
366987;
(Tel
01i34326661;
Fax
01234
326678;France
e-maileuresco@esf
org;
e mailsfam@btinternetcom)
htto
://www.esf.
orq/euresco)
- YfIitl'J{JXfr},1.$3['"0'
ENzyr\,rr
r',TfrE
ENVRTNT\,,ilr
""ryHHHHHnr-
12-lEJuryleee i-'rs'pt'i'r6iijiigg ifll9?f,*fli31fff9,1,Ti3';1;j'
ffi ##ffi#ffi $#*-#ffiyToDAyvoL26/MAy99 IIU
l
Gomment
Yourviewsonthenew
MicrobiologyTday
tookMicrobiology
on a smart and highly professional
lcong.atulations
V
new publication. The first issueof MicrobiologyToday
)AlcrobiologyToday
V
looks extremelvsmart
weekend to read. I thought
suggeststhat it hastransformed from a good publication
in its new design but I am
it was really stupendous.
of the memb ers(The Quarterly) to a magazine that can be
afraidthat for my ageing
You and your team have
passedto non-members for information and opinion on
eyesimproved style has been
certainly made a really
matters of importance. The timing of the articles on GM
excellentiob ofit.
crops was fortuitous and you should run on somespare
achievedat the sacrificeof
readability - main stories I
The' Quarterly' has been
transformed into a really
copiesof those articles for distribution to our opinion-
can just about copewith but
formers. My view of the new format and title is, ofcourse,
MicroShorts, Meetings and
professional,high-class
entirely unbiased by the fact that it contains an article by
Reviews are all something of
magazine for the Society.
one ofour 1998 finalists and the announcement of a Prize
a challenge.
ProfessorRoy R. Russell,,
The Dental School, Un iversity
of N ew castle -upo n -Tyn e
It
J
Todayhomeoverthe
The articles are really very
Lectureship to one ofour staff!
good and comment on
ProfessorNigel L. Brown, Schoolof BiologicalSciences,
really important issues.The
Un iversity of Bi rm ing ham
whole layout is alsovery
[l.i)i.
ihir
't
I
! tIl
r! rf d.oinn.i.i
I jD | !611i)1
rifril,
professionallooking, the
lAbri.fnotero
red bullets are remarkably
V
effective. Pleasefeel free
to passthesehearty
your colleagues on the first
issue of Microbiology Today-
congratulations on to others
in your team. \Well done.
I started at page 1 and read
solidly through to the end -
with the Book Reviews in the last Quararly? I cannot
Professor John C. Fry,
it was absorbing,
bullet points arean irritating mess.Pleasedo not compress
Cardiff Schoolof
interesting and educational.
the text so much in future issuesthen we might seethe
Biosciences
Dr M.O. Moss, Surrey
content.
congratulate you and
Todayis an exrremely disappointing
)ulcrobiology
V
replacement for the .lGM Ouarterly. The font
throughout is too small und in cJtain se.tions has made the
text unreadable.Did anyone open Reviews and compare it
believe they would still havemailed it if they had. The
Mrs D. Wyatt, RegionalVirus Laboratory,
contentsofthe Februaryissueareinreresting,
1|The
V
useful and enjoyable. Howeveq the type gives me
The Queen's Universityof Belfast
problems both for sizeand legibility. In particular the
)tW;croTodaylooks
Vexcellent-welldone
compressed,thin sansseriftype used in legends,news items
and the meetings section is a real problem - and others agree
lcnraru...
Vwelldone.
on agreat job.
Professor NickRusse{
with me. Furthermore, you havereduced the sizeof type for
Reg England, Convener,
M i cro b io Iogy Laborato ri es,
the articles to apoint that is barely tolerable and a bit tiring
Fermentation &
Wye College University of
for people like me. I am appreciativeof the evident intention
Bioprocessing Group
London
to make MicrobiologyToday anecessaryand useful read for
the members, but pleasedo not make it too difficult.
Professor Robert G.E. Murray, Microbiology and
lmmunology, University of Western Ontario, Canada
MT launch
lA
l,rnch was held to mark the launch ofthe new
J
lfhepages
Vpreviously
are much morevisually striking than
and the whole magazinehasa fresh and
magazine.The production and distriburion ream ar
Madborough House was joined by the Editor Dave Roberts,
the designer,Ruth Gregory, from Graphics International
changing font stylesmake the text look busy and the
who was responsiblefor the new look, Ina Cocks from
N\7H Sales,and Paul Yates andJohn Young from \STarwick
squashedupright format is difficult to read. . .
Printers who made such an excellent job of turning the
trendier look about it. You must be very pleasedwith it. The
H oward J en ki n so n, C onve n er,
design into print. \(/e were sorry that the editorial board
Cells &Cell Surtaces Group
members were unable to ioin the celebrations.
The editorial team has taken note of comments on the
style and sizeof rypeface.Thesewill be changed in due
course to improve the readabil ity of MicrobiolagyTod.ay.
Pleaselet us know your views.
llu ffi $#ffi#ffi$*tu#ffiyroDAyvol26/MAy99