Identification of three groups of ginsenoside biosynthetic UDP-glycosyltransferases from Gynostemma pentaphyllum

Abstract

Ginsenoside biosynthetic UGTs have been identified in Panax but not in Gynostemma. Through a biochemical screening of Gynostemma UGTs (GpUGTs), I herein identified three groups of ginsenoside biosynthetic GpUGTs. These groups comprise two GpUGTs that belong to the UGT71 family and glucosylate the C20-OH positions of PPD- and PPT-type ginsenosides

one GpUGT that belongs to the UGT74 family and glucosylates the C3-OH position of PPD-type ginsenosides

and two GpUGTs that belong to the UGT94 family and add glucose to the C3-O-glucosides of PPD-type ginsenosides. These GpUGTs belong to the same UGT families as the ginsenoside biosynthetic Panax UGTs (PgUGTs). However, GpUGTs are not orthologous to PgUGTs. Furthermore, cucumber UGTs orthologous to GpUGTs do not glucosylate ginsenosides. These results collectively suggest that, during evolution, P. ginseng and G. pentaphyllum independently opted to use the same UGT families to synthesize ginsenosides. In addition, I have successfully produce ginsenoside CK and F1 in Arabidopsis thaliana by transforming several ginsenoside biosynthetic genes (PgDs, PgPPDs, PgPPTs, PgUGT71A27, tHMGR). This might suggest the idea to produce ginsenoside faster and more in other organisms than ginseng plants.