CESA_CelA_like are involved in the elongation of the glucan chain of cellulose. Family of proteins related to Agrobacterium tumefaciens CelA and Gluconacetobacter xylinus BscA. These proteins are involved in the elongation of the glucan chain of cellulose, an aggregate of unbranched polymers of beta-1,4-linked glucose residues. They are putative catalytic subunit of cellulose synthase, which is a glycosyltransferase using UDP-glucose as the substrate. The catalytic subunit is an integral membrane protein with 6 transmembrane segments and it is postulated that the protein is anchored in the membrane at the N-terminal end.
CESA_like is the cellulose synthase superfamily. The cellulose synthase (CESA) superfamily includes a wide variety of glycosyltransferase family 2 enzymes that share the common characteristic of catalyzing the elongation of polysaccharide chains. The members include cellulose synthase catalytic subunit, chitin synthase, glucan biosynthesis protein and other families of CESA-like proteins. Cellulose synthase catalyzes the polymerization reaction of cellulose, an aggregate of unbranched polymers of beta-1,4-linked glucose residues in plants, most algae, some bacteria and fungi, and even some animals. In bacteria, algae and lower eukaryotes, there is a second unrelated type of cellulose synthase (Type II), which produces acylated cellulose, a derivative of cellulose. Chitin synthase catalyzes the incorporation of GlcNAc from substrate UDP-GlcNAc into chitin, which is a linear homopolymer of beta-(1,4)-linked GlcNAc residues and Glucan Biosynthesis protein catalyzes the elongation of beta-1,2 polyglucose chains of Glucan.