Reaction: UDP-glucose + a flavonol 3-O-β-D-glucoside = UDP + a flavonol 3-O-β-D-glucosyl-(1→2)-β-D-glucoside
See diagram for reaction with 3-O-β-D-glucosides of kaempferol or quercetin.
Other name(s): UDP-glucose:flavonol-3-O-glucoside 2"-O-β-D-glucosyltransferase
Systematic name: UDP-glucose:flavonol-3-O-β-D-glucoside 2"-O-β-D-glucosyltransferase
Comments: One of three specific glucosyltransferases in pea (Pisum sativum) that successively add a β-D-glucosyl group first to O-3 of kaempferol, and then to O-2 of the previously added glucosyl group giving the 3-O-sophoroside and then the 3-O-sophorotrioside (see also EC 220.127.116.11, flavonol 3-O-glucosyltransferase and EC 18.104.22.168, flavonol-3-O-glycoside glucosyltransferase). TDP-glucose can replace UDP-glucose as the glucose donor but the reaction proceeds more slowly.
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:
1. Jourdan, P.S. and Mansell, R.L. Isolation and partial characterization of three glucosyl transferases involved in the biosynthesis of flavonol triglucosides in Pisum sativum L. Arch. Biochem. Biophys. 213 (1982) 434-443. [PMID: 6462109]