Structure function relationships in plant UDP-glycosyltransferases

Abstract

Uridine diphosphate-dependent glycosyltransferases (UGTs) in plants catalyze O -, C -, S - and N -glycosylation of diverse substrates to yield a wide variety of glycosides with broad bioactivities. Not all wild-type plant UGTs can exhibit excellent catalytic characteristics and achieve application requirements. Desirable enzymes with far greater catalytic properties than the wild type can be obtained through enzyme engineering. Here, we enumerate all currently resolved crystal structures of plant UGTs. The proposed mechanisms for the four types of glycosylation are then summarized. Structure-based protein engineering strategies for improving the catalytic properties of plant UGTs and their principles are further elaborated. Finally, aspects that need in-depth studies and trends for future application of plant UGTs are discussed. • This article itemizes all resolved crystal structures of plant UGTs and proposes mechanisms for four types of glycosylation. • Structure- function relationships are explored under the guidance of protein engineering. • The industrialization prospects and possible future research directions of plant UGTs are clarified.