Small-molecule glucosylation by sucrose phosphorylase: Structure-activity relationships for acceptor substrates revisited

摘要

Sucrose phosphorylase catalyzes the O-glucosylation of awide range of acceptor substrates. Acceptors presenting a suitable 1,2-diol moiety are glucosylated exclusively at the secondary hydroxyl. Production of the naturally occurring compatible solute, 2-O-α-D-glucopyranosyl-sn-glycerol, from sucrose and glycerol is a notable industrial realization of the regio-and stereoselective biotransformation promoted by sucrose phosphorylase. The acceptor substrate specificity of sucrose phosphorylase was analyzed on the basis of recent high-resolution crystal structures of the enzyme. Interactions at the acceptor binding site, observed in the crystal (D-fructosyl) and suggested by results of docking experiments (glycerol), are used to rationalize experimentally determined efficiencies and regioselectivities of enzymatic glucosyl transfer.