XTH-Xet | XET5 Xyloglucan xyloglucosyl transferase

Molecular interactions between wall polysaccharides, which include cellulose and a range of non-cellulosic polysaccharides such as xyloglucans and (1,3;1,4)-?-d-glucans, are fundamental to cell wall properties. These interactions have been assumed to be non-covalent in nature in most cases. A highly purified barley xyloglucan xyloglucosyl transferase HvXET5 (EC 2.4.1.207), a member of the GH16 group of glycoside hydrolases, catalyses the in vitro formation of covalent linkages between xyloglucans and cellulosic substrates, and between xyloglucans and (1,3;1,4)-?-d-glucans. It is possible that XETs could link different polysaccharides in vivo, and hence influence cell wall strength, flexibility and porosity.