A census of carbohydrate-active enzymes in the genome of Arabidopsis thaliana

Publisher Website
Google Scholar
Abstract
The synthesis, modification, and breakdown of carbohydrates is one of the most fundarnentally important reactions in nature. The structural and functional diversity of glycosides is mirrored by a vast array of enzymes involved in their synthesis (glycosyltransferases), modification (carbohydrate esterases ) and breakdown (glycoside hydrolases and polysaccharide lyases). The importance of these processes is reflected in the dedication of 1–2% of an organism’s genes to glycoside hydrolases and glycosyltransferases alone. In plants, these processes are of particular importance for cell-wall synthesis and expansion, starch metabolism, defence against pathogens, symbiosis and signalling. Here we present an analysis of over 730 open reading frarnes representing the two main c1asses of carbohydrate-active enzymes, glycoside hydrolases and glycosyltransferases, in the genome of Arabidopsis thaliana. The vast importance of these enzymes in cell-wall formation and degradation is revealed along with the unexpected dominance of pectin degradation in Arabidopsis, with at least 170 open-reading frarnes dedicated solely to this task. Key words Arabidopsis genome glycoside hydrolases glycosyltransferases