Wall Carbohydrate Composition Research Articles

Screening of Arabidopsis thaliana stems for variation in cell wall polysaccharides

A high-throughput method is described by which Arabidopsis thaliana stems can be screened for variation in cell wall composition after hydrolysis with Driselase or trifluoroacetic acid (TFA). Driselase, a mixture of fungal enzymes, hydrolyses cellulose (to glucose) and all the major matrix polysaccharides (to monosaccharides and/or characteristic disaccharides); TFA hydrolyses the matrix polysaccharides, but not cellulose, to monosaccharides. Two different wild-type ecotypes, Columbia and Wassilewskija, showed only minor differences in wall carbohydrate composition. A small number of T-DNA-tagged populations that were screened contained individuals in which the proportion of cellulose, xyloglucan or xylan differed quantitatively from the wild-type. Differences from the wild-type were also observed in the susceptibility of the hemicelluloses to hydrolysis by Driselase, probably reflecting differences in wall architecture.

Ultrastructural Localization of Carbohydrates in the Cell Walls of Two Pathogenic Fungi: A Comparative Study

A survey of major polysaccharides occurring in cell walls of Ophiostoma ulmi and Verticillium alboatrum was performed by means of gold-complexed lectins and glycosidic enzymes. Some differences in wall carbohydrate composition and distribution were noted in these fungi. Both chitin and cellulose were found to occur in the walls of 0. ulmi whereas only chitin was present in those of V. albo-atrum. Polygalacturonic acids were identified in both fungi but a greater amount of galactose and N-acetyl-Dgalactosamine residues occurred in the walls of V. albo-atrum. In contrast, a-mannosyl and/or a-glucosyl groups were detected only in 0. ulmi cell walls. /-glucosides and sialic acid were absent in the walls of both fungi.