Ferulate polysaccharide esters in grasses enter into free-radical condensation reactions in the cell wall. By radical dimerisation of ferulates, polysaccharide-polysaccharide cross-linking is eΓΎ ected. A range of diferulate isomers are produced, not solely the 5-5ΒΊ-coupled dimer which has been quant
Biosynthesis of cell-wall ferulate and diferulates
β Scribed by Brett, Christopher T; Wende, Gundolf; Smith, Andrew C; Waldron, Keith W
- Publisher
- John Wiley and Sons
- Year
- 1999
- Tongue
- English
- Weight
- 89 KB
- Volume
- 79
- Category
- Article
- ISSN
- 0022-5142
No coin nor oath required. For personal study only.
β¦ Synopsis
Cell-wall hydroxycinnamates are derived from feruloyl-CoA, coumaroyl-CoA and other intermediates of the phenylpropanoid pathway. In normal (unelicited) tissues, hydroxycinnamates are ester-linked to pectins in some dicots and to arabinoxylans in grasses. The ester-linked hydroxycinnamates are thought to be formed by feruloylation of nascent polysaccharides in the Golgi apparatus, feruloyl-CoA perhaps being the substrate. It is not known whether dimerisation of polysaccharide-linked ferulate occurs in the Golgi apparatus as well as in the wall. In elicited dicot cells the immediate precursors of wall ferulate and coumarate include low molecular weight hydroxycinnamate derivatives (amides and esters) which are secreted into the cell wall and then oxidatively linked to polymers. The cell-wall hydroxycinnamates may, in some circumstances, be subject to turnover, though this may be a property of suspension cultured cells that is not necessarily shared with normal plant tissues.
π SIMILAR VOLUMES
Enzymatic hydrolysis of sugar-beet pulp, and subsequent isolation of feruloylated oligosaccharides, has shown that ferulic acid groups are ester-linked mainly on O-2 of arabinose residues and on O-6 of galactose residues in the pectin side-chains. After saponiΓΌcation of sugar-beet pulp enzymatic dig