Structure of the Universe

Structure of the Universe
10. Origin and Evolution of Life
Michał Kurzyński
Faculty of Physics, A. Mickiewicz University
26
10 m
7
6
Hubble length
8
Planetary system
9
Planet
10, 1
Human
2, 3, 4
Atom
Atomic nucleus
5
-35
7
10 m
Planck length
1
Main elements
l = 0 (s)
l = 1 (p)
n=1
H
He
n=2
Li
Be
B
C
N
O
F
Ne
n=3
Na Mg Al
Si
P
S
Cl
Ar
• atmosphere: CO2 , hydrosphere: H2O
• lithosphere: (SiO4)4−, (AlO4)5−, (AlO6)9−
• biosphere: lipids, proteins, nucleic acids, polysaccharides
• ionic equilibr: Ca2+, Mg2+, Na+, K+, Cl−, Fe2+/Fe3+, Cu+/Cu2+
Lipids (a), proteins (b), nucleic acids (c),
polysaccharides (d)
(a)
R
-
+
CO O H H O
H
H
R'
R
CO
O
R
CO
NH
R'
H2O
(b)
R
CO O
H
- +
H2 NH
H
R'
R'
H2O
(c)
R
O
PO
H
-
-
2
+
O H HO
H
R
R'
O
-
POH2
H
O
H
R'
H2O
(d)
O
HC
H
OH H O
O
HC
R'
O
R
H2O
endoergic reactions, ATP the source of free energy
2
Phospholipids
-
+
-
+
R1
CO
H O H HHO
R2
CO O H HHO
H
O
PO
H
hydrophobic
(a)
glycerol
OH
-
2
+
HOO R3
O H H
hydrophilic
(c)
H
O
O
HO
OH
Bi
H
OH
O
O
OH
O
HO
O
O
OH
O
OH
OH
X
-
PO 2O
OH
OH
O
B
Hi +1
(b)
R
Hi
H
O
CO
H
O
NH
O
H
Ri +1
X
H
3
Hydrogen bonds: α helix
http://www.denizyuret.com/students/vkurt/thesis-main_dosyalar/image010.jpg
Hydrogen bonds: β-sheets
http://www.denizyuret.com/students/vkurt/thesis-main_dosyalar/image012.jpg
4
http://news.uns.purdue.edu/uns/images/cramer.photo2.jpeg
Lipid bilayer
& proteins
Old model
An amended and
updated version
(clustering of proteins,
anomalous diffusion)
D. M. Engelman,
Nature 438, 578 (2005)
5
DNA – double chain
http://upload.wikimedia.org/wikipedia/commons/thumb/4/4c/DNA_Structure%2BKey%2BLabelled.pn_
NoBB.png/800px-DNA_Structure%2BKey%2BLabelled.pn_NoBB.png
RNA – single chain
http://www.cgm.cnrs-gif.fr/michel/images/fig1.gif
www.cgm.cnrs-gif.fr/michel/images/fig2.jpg
6
RNA & proteins
Ribosome
(endoplasmic
reticulum)
partly in membrane,
partly in water
http://www.beckman.illinois.edu/news/releases/images/release0914073.jpg
DNA & proteins
Nucleosome
(chromatin in
the nucleus)
http://www.leavethelightson.info/data/site/nucleosome.png
7
Beginning of life
• Primordial soup: H2, CH4, NH3, H2O
• Meteorites
• Black smokers (acidic sea vents)
• White smokers (alkaline sea vents)
Deep sea vents life in the Mid-Atlantic Ridge
http://www.redorbit.com/media/gallery/national-science-foundation-gallery/
183_53b0b292cd83b84b0d674620b3d97074.jpg
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Black smokers
Acidic H2S – energy
source for life
Wachtershauser
(1988 – 1992)
http://media1.s-nbcnews.com/j/MSNBC/
Components/Photo/new/130111-LifePhotohmed-1205p_files.grid-5x2.jpg
White smokers
Alkaline reductor Fe2+(OH)-2 –
source of H2 and CH4 – reacts
with acidic water HCO3CaCO3 is formed
Michael Russel (1988)
Lost City (hydrothermal field)
http://www.nsf.gov/od/lpa/news/press/01/pr0156.htm
9
Life
(a)
replication
DNA
transcription
translation
RNA
protein
replication
in RNA-viruses
(b)
DNA
RNA
reverse
transcription
in retroviruses
protein
prions
10
RNA World
Chicken-and-egg problem: what was the first,
proteins or DNA?
Answer (Eigen): RNA is not only the information
carrier (genotype) but also an object of selection
(phenotype). It can also spontaneously polymeryze
on the already existing RNA template.
Hence, it is living!
•RNAs as catalysts (selfsplicing, ribosomes)
•RNA interference
•Reversible transcriptases
•Ribonucleoside triphosphates are the source of free energy
•Diribonucleotides are co-factors in many protein enzymes
RNA protection –
utilization of lipids and proteins
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(a)
(b)
(c)
mRNA
NTP
DNA
transcriptase
tRNA
NTP
rRNA
replicase
RNA
mRNA
protein
(d)
glucose
+
NAD
(f)
(e)
pyruvate
NAD
ADP+Pi
NADH
+
+H
pyruvate
ATP
H
+
lactate + H
CO2
+
+
NADH
+
+H
H
ATP
ATP
ADP+Pi
ADP+Pi
+
H
+
C6H12O6 + 6H2O → 6CO2 + 12H2
(a)
(b)
3H +
2H+
ATP
H + + NADH
ADP + P
+
interior
2H+
NAD
interior
2e-
Q
2eNO3-
3H +
NO2 + H2O
2H+
2H+
Other oxidants: NO2-, HCO3-, SO42Other reducers: H2, CH4, NH3, H2S
(chemotrophy – hydrothermal vents at the oceanic rifts)
12
H+-ATPase
= ATP syntase
J. Weber, BBA 1757, 1162 (2007)
A. Y. Mulkidjanian et al.,
Nature Revs. 5, 892 (2007)
13
Hydrogen carrier: NAD+
soluble in water
Hydrogen carrier: quinone
(Q10) soluble in fat
wikipedia/commons/thumb
cyanobacteria / chloroplasts
2H+
NADP +
2H+
2H+
Fd
interior
PS II
2eH2O
1
-2 O2
Q
PS I
cyt bf
2e-
PC
2e-
H + + NADPH
2e-
4H+
2H
+
14
aerobic bacteria / mitochondria
2H+
H + + NADH
4H+
2H+
+
NAD
interior
Q
2e-
cyt bc1
cyt aa3
-
2e
c
2e-
2H+
1
-2 O2
H2O
4H+
2H+
Archaebacteria
halophiles
methanogens
thermophiles
Eukaryota
fungi
chromatin
animals
protista
centrioles mitochondria chloroplasts
plants
Eubacteria
Gram-positive
spirochetes
purple
aerobic
green
cyanobacteria
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rzêska (krótka)
wiæ (d³uga)
centriole
g³adkie
retikulum endoplazmatyczne
j¹dro
ziarno
wodniczka
szorstkie
retikulum endoplazmatyczne
tylakoid
aparat Golgiego
mitochondrium
chloroplast
egzosom
lizosom
œciana komórkowa
endosom
• ? – eukaryotic cell: nucleus and mitotic cell division.
Sex: doubling of genetic information, meiotic division
• 1.0 billion years ago – embryo that differentiates into
a multicellular organism
• 540 million years ago – skeletons from calcium
carbonate or silicate (fossils). The Cambrian explosion,
beginning of Paleolithic era
• 440 million years ago – symbiosis of plants and fungi
allows their emergence on land
• 300 - 280 million years ago – the last Pangea, the
Carboniferous/Permian glaciation
• 100 milltion years ago – protecting the embryo:
angiospermous plants and mammals with placenta
• 6 million years ago – first hominid
• 2.6 million years ago – beginning of Pleistocene,
glacial cycles influence evolution of men
• 150 thousand years ago – first Homo sapiens
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