Lecture Nineteen Lipids -- Introduction, Synthesis of Fatty Acids, Waxes and Cutin
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Waxes and Cutin Purpose and Outline The purpose of today's lecture/discussion is introduce some aspects of the biological chemistry of plant glycerolipids you likely didn't study previously. We will also review saturated fatty acid biosynthesis with emphasis on aspects unique to plants. Finally we will briefly cover the synthesis of waxes and cutin in plants. Reading Assignment for the First Lipids Discussion for Class: a) REQUIRED: 1- Gniwotta, F., G. Vogg, V. Gartmann, T.L.W. Carver, M. Riederer, and R. Jetter. 2005. What Do Microbes Encounter at the Plant Surface? Chemical Composition of Pea Leaf Cuticular Waxes. Plant Physiol. 139 : 519-530 . 2- Kroumova, A.B., Z. Xie and G.J.Wagner. 1994. A pathway for the biosynthesis of straight and branched, odd- and even-length, medium-chain fatty acids in plants. Proc. Natl. Acad. Sci. USA 91: 11437-11441. 3- Chapter 10, pp 456-476, of the Biochemistry & Molecular Biology of Plants class text. b) OPTIONAL: 1- Yu, B. and C. Benning. 2003. Anionic lipids are required for chloroplast structure and function in Arabidopsis. The Plant Journal. 36: 762-770. 2- <![endif]>Sakurai, I., M. Hagio, Z. Gombos, T. Tyystjarvi, V. Paakkarinen, E.-M. Aro and H. Wada. 2003. Requirement of Phosphatidylglycerol for Maintenance of Photosynthetic Machinery. Plant Physiol. 133: 1376-1384. 3- Dehesh, K., H. Tai, P. Edwards, J. Byrne and J.G. Jaworski. 2001. Overexpression of 3-ketoacyl-acyl- carrier protein synthase IIIs in plants reduces the rate of lipid biosynthesis. Plant Physiology 125: 1103- 1114. 4- Focks, N. and C. Benning. 1998. wrinkled 1: A novel, low-seed-oil mutant of Arabidopsis with a deficiency in the seed-specific regulation of carbohydrate metabolism. Plant Physiol. 118:91-101. 5- Martinez-Force, E. and R. Garces. 2002. Dynamic channelling during de novo fatty acid biosynthesis in Helianthus annuus seeds. Plant Physiology and Biochemistry 40: 383-391. 6- Ohlrogge, J.B. and J.G. Jaworski. 1997. Regulation of fatty acid synthesis. Annu. Rev. Plant Physiol. Plant Molec. Biol. 48:109-136.
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Lecture Nineteen Lipids -- Introduction, Synthesis of Fatty Acids, Waxes and Cutin Purpose and Outline - PowerPoint PPT Presentation
Transcript of Lecture Nineteen Lipids -- Introduction, Synthesis of Fatty Acids, Waxes and Cutin
Lecture Nineteen Lipids -- Introduction, Synthesis of Fatty Acids, Waxes and Cutin
Purpose and Outline
The purpose of today's lecture/discussion is introduce some aspects of the biological chemistry of plant glycerolipids you likely didn't study previously. We will also review saturated fatty acid biosynthesis with emphasis on aspects unique to plants. Finally we will briefly cover the synthesis of waxes and cutin in plants.
Reading Assignment for the First Lipids Discussion for Class: a) REQUIRED:
1- Gniwotta, F., G. Vogg, V. Gartmann, T.L.W. Carver, M. Riederer, and R. Jetter. 2005. What Do Microbes Encounter at the Plant Surface? Chemical Composition of Pea Leaf Cuticular Waxes. Plant Physiol. 139: 519-530.
2- Kroumova, A.B., Z. Xie and G.J.Wagner. 1994. A pathway for the biosynthesis of straight and branched, odd- and even-length, medium-chain fatty acids in plants. Proc. Natl. Acad. Sci. USA 91: 11437-11441.
3- Chapter 10, pp 456-476, of the Biochemistry & Molecular Biology of Plants class text.
b) OPTIONAL:
1- Yu, B. and C. Benning. 2003. Anionic lipids are required for chloroplast structure and function in Arabidopsis. The Plant Journal. 36: 762-770.
2- <![endif]>Sakurai, I., M. Hagio, Z. Gombos, T. Tyystjarvi, V. Paakkarinen, E.-M. Aro and H. Wada. 2003. Requirement of Phosphatidylglycerol for Maintenance of Photosynthetic Machinery. Plant Physiol. 133: 1376-1384.
3- Dehesh, K., H. Tai, P. Edwards, J. Byrne and J.G. Jaworski. 2001. Overexpression of 3-ketoacyl-acyl-carrier protein synthase IIIs in plants reduces the rate of lipid biosynthesis. Plant Physiology 125: 1103-1114.
4- Focks, N. and C. Benning. 1998. wrinkled 1: A novel, low-seed-oil mutant of Arabidopsis with a deficiency in the seed-specific regulation of carbohydrate metabolism. Plant Physiol. 118:91-101.
5- Martinez-Force, E. and R. Garces. 2002. Dynamic channelling during de novo fatty acid biosynthesis in Helianthus annuus seeds. Plant Physiology and Biochemistry 40: 383-391.
6- Ohlrogge, J.B. and J.G. Jaworski. 1997. Regulation of fatty acid synthesis. Annu. Rev. Plant Physiol. Plant Molec. Biol. 48:109-136.
Lipid: ___________________
O O
OH
OHOH
HOH2C
H
C
C
CH
O
OR1
R2
H
H
H
O
OOH
OH
OH
HOH2C
O O
OH
OH
OH
CH2
H
C
C
CH
O
OR1
R2
H
H
H O O
OH
OHOH
CH2
H
C
C
C
H
O
OR1
R2
H
H
H
HO3S
H C C C O
HOO
R1 R2
H H H
O
P O
OHC C
HH
H H
N(CH3)3+ H C C C O
HOO
R1 R2
H H H
O
P O
OH
C C
HH
H H
NH2
H C C C O
HOO
R1 R2
H H H
O
P O
OH
C C
COOHH
H H
NH2 H C C C O
HOO
R1 R2
H H H
O
P O
OH
C C
OHH
H H
C
H
H
OH
OHOH
OH
OH
H
C
C
C
H
O
OR1
R2
H
H
HOH
O
P O
OH
O
H C C C H
OO
FA FA
H H
H
OPHO
O
H C C C O
HOO
R1 R2
H H H
O
P O
OH
C C
OHH
H H
C
H
O
H
O CH3
NH2
OH
O CH3
NH
OH
O R
R
R
Fatty acids:
Formula (chemical name)common name
# Carbons
HCOOH formic acid 1CH3COOH acetic acid 2
CH3CH2COOH proprionic 3CH3(CH2)2COOH butyric 4
CH3(CH2)3COOH (pentanoic)valeric 5
CH3(CH2)4COOH (hexanoic)caproic 6
CH3(CH2)5COOH heptanoic 7
CH3(CH2)6COOH (octanoic)caprylic 8
CH3(CH2)7COOH nonanoic 9
CH3(CH2)8COOH (decanoic)capric 10
CH3(CH2)9COOH undecanoic 11
CH3(CH2)10COOH (____________)lauric 12
CH3(CH2)11COOH tridecanoic 13
CH3(CH2)12COOH (____________)myristic 14
CH3(CH2)13COOH pentadecanoic 15
Table 1. Short and medium chain fatty acids.
Table 2. Important long-chain fatty acids:
(hexadeca-noic)palmitic16:0
(cis 7-hexadecenoic) [palmitoleic(9)]16:1
7,10-hexadecadie-noic16:2
7,10,13-hexadecatrienoic(roughanic)16:3
Heptadeca-noic17:0
(_____________)stearic18:0
(9-octadecenoic)oleic acid18:1
(9,12-octadecadienoic)linoleic18:2
(9,12,15-octadecatrienoic)linolenic acid18:3
Nonadeca-noic19:0
(eicosanoic)arachidic20:0
(5,8,11,14-eicosatetraenoic)arachidonic20:4 [ ]
(5,8,11,14,17-eicosapentaenoic)timnodonic; EPA20:5
(docosanoic)behenic22:0
(13-docosenoic)erucic22:1 [ ]
(4,7,10,13,16,19-docosahexaenoic)cervonic; DHA22:6
(tetracosa-noic)lignoceric24:0
(15-tetracosenoic)nervonic24:1
waxes & cuticular lipids
O
O
CH3
O
O
CH3
O
O
CH3
O
O
CH3
O
O
CH3
O
O
CH3
H C C C Head Group
HOO
R1 R2
H H H
-
-
-
-
-
-
or R3
KAS = TE = DS = AT =
What is the source of the acetyl-CoA?
Why is it that the reaction stops at C16 and C18 fatty acids?
a) REQUIRED:
1 - Engelman, D.M. 2005. Membranes are more mosaic than fluid. Nature 438: 578-580.2 - Voelker, T. and A.J. Kinney. 2001. Variations in the Biosynthesis of Seed-Storage Lipids. Annual Review of Plant Physiology and Plant Molecular Biology 52: 335-361.3 - Chapter 10, sections 10.5 - 10.8 and 10.10.1 -10.10.3, of the Biochemistry & Molecular Biology of Plants class text.
b) OPTIONAL:
1 - Broun et al. 1998. Catalytic plasticity of fatty acid modification enzymes underlying chemical diversity of plant lipids. Science 282:1315-1317. 2 - Shanklin, J. and Cahoon, E.B. 1998. Desaturation and related modifications of fatty acids. Annu. Rev. Plant Physiol. Plant Molec. Biol. 49:611-641. 3 - Beisson, F., A. J. K. Koo, S. Ruuska, J. Schwender, M. Pollard, J. J. Thelen, T. Paddock, J. J. Salas, L. Savage, A. Milcamps, V. B. Mhaske, Y. Cho and J. B. Ohlrogge. 2003. Arabidopsis Genes Involved in Acyl Lipid Metabolism. A 2003 Census of the Candidates, a Study of the Distribution of Expressed Sequence Tags in Organs, and a Web-Based Database. Plant Physiol. 132: 681-697. 4 - McMahon, H.T., and J.L. Gallop. 2005. Membrane curvature and mechanisms of dynamic cell membrane remodelling. Nature 438:590-596. 5 - Murakami et al. 2000. Trienoic fatty acids and plant tolerance of high temperature. Science 287:477-479.6 - Dahlqvist, A., U. Stahl, M. Lenman, A. Banas, M. Lee, L. Sandager, H. Ronne and S. Stymne. 2000. Phospholipid:diacylglycerol acyltransferase: An enzyme that catalyzes the acyl-CoA-independent formation of triacylglycerol in yeast and plants. Proc. Natl. Acad. Sci. USA 97: 6487-6492.
Reading Assignment for the second lipid lecture:
