Accepted name: α-1,3-glucan synthase
Reaction: UDP-glucose + [α-D-glucosyl-(1→3)]n = UDP + [α-D-glucosyl-(1→3)]n+1
Other name(s): uridine diphosphoglucose-1,3-α-glucan glucosyltransferase; 1,3-α-D-glucan synthase; UDP-glucose:α-D-(1-3)-glucan 3-α-D-glucosyltransferase
Systematic name: UDP-glucose:α-D-(1→3)-glucan 3-α-D-glucosyltransferase
Comments: A glucan primer is needed to begin the reaction, which brings about elongation of the glucan chains.
1.  Andoh, M., Yamashita, Y., Shigeoka, T., Hanada, N. and Takehara, T. [Extension of the length of glucan chain by 1,3-α-D-glucansynthase from Streptococcus mutans serotype.] Koku Eisei Gakkai Zasshi 37 (1987) 516–517.
[EC created 1990]