This enzyme belongs to the family of transferases, specifically those acyltransferases transferring groups other than aminoacyl groups. The systematic name of this enzyme class is 1-O-galloyl-beta-D-glucose:1-O-galloyl-beta-D-glucose O-galloyltransferase.
Denzel K, Schilling G and Gross, GG (1988). "Biosynthesis of gallotannins - enzymatic conversion of 1,6-digalloylglucose to 1,2,6-trigalloylglucose". Planta176: 135–137. doi:10.1007/BF00392489.
Gross, GG (1983). "Synthesis of mono-galloyl-beta-D-glucose di-galloyl-beta-D-glucose and trigalloyl-beta-D-glucose by beta-glucogallin-dependent galloyltransferases from oak leaves". Z. Natursforsch. C: Biosci.38: 519–523.