Cell wall polysaccharide composition and covalent crosslinking: Freely available at doi: 10.1002/9781444391015.ch1

Research output: Chapter in Book/Report/Conference proceedingChapter (peer-reviewed)

Abstract

Genetics now potentially lets us modify the production, cross-linking and degradation of cell-wall polysaccharides. There remains, however, the need to test experimentally whether intended modifications of polysaccharide metabolism have successfully been effected in vivo. Simple methods for this are described, including in-vivo radiolabelling, enzymic dissection e.g. with Driselase, and chromatographic/electrophoretic fractionation of dissection-products.
After an overview of polysaccharide chemistry, I discuss the structures and taxonomic distribution of wall polysaccharides in charophytes and land plants. Primary and secondary walls are compared.
The major wall polysaccharides are cellulose [microfibrillar -(14)-D-glucan], pectins (-D-galacturonate-rich) and hemicelluloses (lacking galacturonate; hydrogen-bonding to cellulose; extractable by 6M NaOH at 37°C). Land-plant pectins are anionic polymers built of ~4 glycosidically interconnected domains (homogalacturonan, rhamnogalacturonans I and II, xylogalacturonan). Hemicelluloses occurring in most/all land plants are -xylo--glucans, -xylans (including -arabino--xylans, -glucurono--xylans etc.), and -mannans (including -galacto--mannans, -gluco--mannans etc.). Another hemicellulose [mixed-linkage -(13)(14)-D-glucan) is confined to Equisetum and some Poales.
Other taxonomically restricted features of angiosperm primary walls occur in Poales (xylose-poor xyloglucans; feruloylated arabinoxylans); Solanales and Lamiales (characteristic xyloglucans); Caryophyllales (feruloylated pectins); and Alismatales (apiogalacturonan). I also summarise characteristic wall features of charophytes, bryophytes, lycopodiophytes, fern-allies and gymnosperms.
Making/breaking of a ‘cross-link’ (=an individual type of chemical bond, not a whole ‘tethering’ chain) may cause wall tightening/loosening. Covalent cross-links include phenolic coupling-products; uronoyl esters and amides; and borate diesters.
Original languageEnglish
Title of host publicationAnnual Plant Reviews
Subtitle of host publicationPlant Polysaccharides, Biosynthesis and Bioengineering
EditorsPeter Ulvskov
PublisherOxford:Wiley-Blackwell
Pages1-42
Number of pages42
Volume41
Publication statusPublished - 2011

Fingerprint

Dive into the research topics of 'Cell wall polysaccharide composition and covalent crosslinking: Freely available at doi: 10.1002/9781444391015.ch1'. Together they form a unique fingerprint.

Cite this