Lecture PBPM - Secondary plant cell wall

Lecture PBPM - Secondary plant cell wall

Lecture PBPM - Secondary plant cell wall
Secondary plant cell wall
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Lecture PBPM - Secondary plant cell wall: topics
Topics
plant/environment interface of cutin (lipophilic biopolymer)
fine structure of leaf surfaces
chemical composition of cutin and wax
lipid and wax biosynthesis
cuticle structure
plant/environment
l / i
interface
i
f
off suberin
b i (lipophilic
(li
hili biopolymer)
bi
l
)
chemical composition of suberin
biosynthesis of suberin
occurrence and fine structure of suberized cell walls
lignin
g
as an aromatic biopolymer:
p y
mechanical stability
y of p
plants
lignin monomers and lignin biosynthesis
lignin polymerisation
lignin structure
histochemical detection of lignin
lignification and pathogen defence
2/34
Lecture PBPM - Fine structure of leaf surfaces covered by cuticles
Caltha palustris
Anthemis tinctoria
Viola tricolor
C l h palustris
Caltha
l
i
P th
Parthenocissus
i
tricuspidata
ti
id t
N
Neoporteria
t i brevicylindrica
b i li d i
3/34
Lecture PBPM - Fine structure of leaf surfaces covered by waxes
Taxus baccata
Heliconia collinsiana
Lonicera tatarica
Hypericum buckleyi
Lecythis chartacea
Williamodendron quadrilocelathum
4/34
Lecture PBPM - Wax covered stomate
5/34
Lecture PBPM - Wax mutants of Arabidosis thaliana help to identifying wax biosynthesis genes
wt
stem
cer7
cer 17
wt
silique
cer7
cer 17
6/34
Lecture PBPM - Cuticle of Clivia nobilis in the light microscope
cell wall staining
cutin staining
cell wall and
cutin stainingg
7/34
Lecture PBPM - Cuticle in the transmission electron microscope: glandular cell of Lamium
cuticle
cell wall
cell
8/34
Lecture PBPM - Relative distribution of lipids in leaves
9/34
Lecture PBPM - Proposed pathway for wax biosynthesis
10/34
Lecture PBPM - Major constituents of cutin and wax
ω-hydroxyfatty
ω
hydroxyfatty acids
in chain-hydroxyfatty acids
h i llengths
th off
chain
C16 and C18
waxes can have chain lengths
between C22 to C60
11/34
Lecture PBPM - Proposed poylmer structure of cutin
12/34
Lecture PBPM - Epidermis covered by a cuticle
13/34
Lecture PBPM - Suberized interfaces of plants
14/34
Lecture PBPM - Suberin and lenticells
15/34
Lecture PBPM - Suberin biosynthesis
OH
H 3C
n
H 3C
OH
n
H 3C
P450?
KCS
(FDH, HIC, KCS1 ?)
R
P450
C
H 3C
n
FAD
H 3C
R
S CoA
COOH
H
H
O
C
C
C
H
H
HO
n
P450
• elongation – FAE (KCS)
O
C
C
S C oA
H
OH H
O
C
C
C
H
H
S CoA
S C oA
O
C
C
H
H
C
S C oA
COOH
ω-hydroxyacid dehydrogenase
(HTH ?)
O
n
• functionalisation – P450
H
C
R
R
(LCR, ATT1 ?)
O
FAE
C24
C22
C20
C18
P450
COOH
n
R
O
COOH
n
OH
FAR
P450
COOH
COOH
ω-oxo-acid dehydrogenase
OH
O
n
COOH
16/34
Lecture PBPM - Major constituents of suberin
ω hydroxyfatty acids of various chain lengths
ω-hydroxyfatty
α,ω-diacids of various chain lengths
chain lengths can vary between C16 to C32
17/34
Lecture PBPM - Stem periderm of Malus sylvestris
18/34
Lecture PBPM - Belowground suberized interfaces of plants in roots
19/34
Lecture PBPM - Suberin ultra structure of potato periderm (Solanum tuberosum)
20/34
Lecture PBPM - Lignified cell walls of Asparagus officinalis in the light microscope
21/34
Lecture PBPM - Histochemical detection of lignin
22/34
Lecture PBPM - Biosynthesis of phenolics leading to lignin monomers: easy scheme
23/34
Lecture PBPM - Biosynthesis of phenolics leading to lignin monomers: detailed scheme
p-Coumaryl alcohol
Coniferyl alcohol
Sinapyl alcohol
24/34
Lecture PBPM - Radical polymerisation of lignin
peroxidase
coniferyl
if l
alcohol
isomeric forms the coniferyl alcohol radicals
25/34
Lecture PBPM - Lignin monomers and the polymer
compound
p-coumaryl alcohol
coniferyl alcohol
sinapyl alcohol
26/34
Lecture PBPM - Hypothetical structure of the lignin polymer
27/34
Lecture PBPM - Architecture of a conifer tracheid from Pseudotsuga menziesii
28/34
Lecture
Lecture PBPM -- Lignification as important defence reaction of plants towards pathogens
fungus
epidermal cell
29/34