An efficient chemoenzymatic production of small molecule glucosides with in situ UDP-glucose recycling

A one-pot system for efficient enzymatic synthesis of curcumin glucosides is described. The method couples the activities of two recombinant enzymes, UDP-glucose: curcumin glucosyltransferase from Catharanthus roseus (CaUGT2) and sucrose synthase from Arabidopsis thaliana (AtSUS1). UDP, a product inhibitor of UDP-glucosyltransferase, was removed from the system and used for regeneration of UDP-glucose by the second enzyme, AtSUS1. The productivity was increased several-fold and UDP-glucose initially added to the reaction mixture could be reduced to one-tenth of the normal level. The concept of enhancing glucosylation efficiency by coupling a UDP-glucose regeneration system with glucosyltransferases should be applicable to enzymatic production of a wide range of glucosides.