In enzymology, a cellulose synthase (UDP-forming) (EC 22.214.171.124) is an enzyme that catalyzes the chemical reaction
Thus, the two substrates of this enzyme are UDP-glucose and a chain of 1,4-beta-D-glucosyl residues, whereas its two products are UDP and an elongated chain of glucosyl residues. Glucosyl is the glycosyl of glucose, a chain of 1,4-beta-D-glucosyl residues is cellulose, and enzymes of this class therefore play an important role in the synthesis of cellulose.
This enzyme belongs to the family of hexosyltransferases, specifically to the glycosyltransferases. The systematic name of this enzyme class is UDP-glucose:1,4-beta-D-glucan 4-beta-D-glucosyltransferase. Other names in common use include UDP-glucose-beta-glucan glucosyltransferase, UDP-glucose-cellulose glucosyltransferase, GS-I, beta-1,4-glucosyltransferase, uridine diphosphoglucose-1,4-beta-glucan glucosyltransferase, beta-1,4-glucan synthase, beta-1,4-glucan synthetase, beta-glucan synthase, 1,4-beta-D-glucan synthase, 1,4-beta-glucan synthase, glucan synthase, UDP-glucose-1,4-beta-glucan glucosyltransferase, and uridine diphosphoglucose-cellulose glucosyltransferase.