Plant cell wall proteins (CWPs) progressively emerged as crucial components of cell walls although present in minor amounts. Cell wall polysaccharides such as pectins, hemicelluloses, and cellulose represent more than 90% of primary cell wall mass, whereas hemicelluloses, cellulose, and lignins are the main components of lignified secondary walls. All these polymers provide mechanical propertie...

The enlargement of plant cell walls is a key determinant of plant morphogenesis. Current models of the cell wall are reviewed with respect to their ability to account for the mechanism of cell wall enlargement. The concept of primary and secondary wall loosening agents is presented, and the possible roles of expansins, xyloglucan endotransglycosylase, endo-1,4-beta-D-glucanase, and wall synthes...

Plants are the sources of major food, feed, and fiber products that are used globally. This past year has seen advances in our understanding of the enzymes that modify wall architecture, the cloning of the first cellulose synthase gene, and revisions to the lignin biosynthetic pathway. These discoveries have facilitated the development of new strategies to alter cell wall properties in transgen...

For a plant to grow properly it has to detect and respond appropriately to a diverse set of signals that emanate from the cell wall. A novel receptor-like kinase has recently been identified as essential in this process.

Intact Bacillus megaterium cells were found to contract as much as 26% in terms of dextran-impermeable volume when transferred from water to unbuffered, non-plasmolyzing NaCl solutions. This shrinkage appeared to be primarily due to electrostatic wall contraction rather than to any osmotic response of the cells. A variety of salts (but not sucrose) added to water suspensions of isolated cell wa...

Unlignified primary cell walls containing ester-linked ferulic acid fluoresce blue in ultraviolet radiation which changes to green with increased intensity on treatment with ammonium hydroxide. Using this fluorescence behaviour, we detected ester-linked ferulic acid in the primary cell walls of all 41 species of gymnosperms we examined. These species were in 17 families representing all four ex...