Biosynthesis of Suberin

Phenolic acids and aliphatic acids are both involved in the biosynthesis of suberin, and phenolic acids are not synthesized in tissue slices that do not undergo suberization. 

The mid-chain oxygenated fatty acids that are found in some suberin polymers are generated by the biosynthetic pathways shown in Fig. 6.4.10. Although these pathways have been demonstrated by studies with cell-free preparations of cutin-synthesizing systems, similar reactions are most probably involved in the biosynthesis of suberin monomers. 

A333 Biosynthesis of Suberin from Aliphatic and Aromatic Monomers... 

Kolattukudy PE, Espelie KE (1985) Biosynthesis of cutin, suberin, and associated waxes. In Higuchi T (ed) Biosynthesis and biodegradation of wood components. Academic Press, New York p 161... 

The functions of phenylpropanoid derivatives are as diverse as their structural variations. Phenylpropanoids serve as phytoalexins, UV protectants, insect repellents, flower pigments, and signal molecules for plant-microbe interactions. They also function as polymeric constituents of support and surface structures such as lignins and suberins [1]. Therefore, biosynthesis of phenylpropanoids has received much interest in relation to these functions. In addition, the biosynthesis of these compounds has been intensively studied because they are often chiral, and naturally occurring samples of these compounds are usually optically active. Elucidation of these enantioselective mechanisms may contribute to the development of novel biomimetic systems for enantioselective organic synthesis. 

Kolattukudy, P. E. Espelie, K. E. Biosynthesis of Cutin, Suberin and Associated Waxes In Biosynthesis and Biodegradation of Wood Components Higuchi, T., Ed Academic Press New York, 1985 pp. 161-207. 

Davin, F.B. and Lewis, N.G. (1992) Phenylpropanoid metabolism biosynthesis of monolignols, lignans and neolignans, lignins and suberins, in Phenolic Metabolism in Plants (eds H.A. Stafford and R.K. Ibrahim). Plenum, New York, pp. 325-75. 

L. B. Davin N. G. Lewis, Phenylpropanoid Metabolism Biosynthesis of Monolignols, Lignans and Neolignans, Lignins and Suberins. In Recent Advances in Phytochemistry] Vol. 26 Phenolic Metabolism in Plants H. A. Stafford, R. K. Ibrahim, Eds. Plenum Press New York, 1992 pp 325-375. 

Components of membrane transformation systems include the nucleus with its DNA, nonhistone chromosomal proteins, and the derived informational molecules (e.g., mRNA) for protein synthesis. The mRNA moves into the cytoplasm through the transformation of membranes. For example, the rough endoplasmic reticulum contains ribosomal RNA with its templates for protein synthesis. The system evolves with cytoplasmic organelles and substrates to influence structure and function. During this process the vacuoles, microtubules, endoplasmic reticulum, subcellular organelles, and plasmalemma may release specific metabolic nitrogenous products (conjugates, enzymes) internally or externally. Some of these may be involves in the biosynthesis of cutin and suberin (76). 

Fig. 6.4.9. Biosynthetic pathways for the major aliphatic components of suberin and some essential elements of the active site of w-hydroxy fatty acid dehydrogenase, a key enzyme in suberin biosynthesis (5)...

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