Glycosyltransferases catalyze glycosidic bond formation using sugar donors containing a
nucleoside phosphate or a lipid phosphate leaving group. Only two structural folds, GT-A
and GT-B, have been identified for the nucleotide sugar-dependent enzymes, but other folds
are now appearing for the soluble domains of lipid phosphosugar-dependent glycosyl
transferases. Structural and kinetic studies have provided new insights. Inverting
glycosyltransferases utilize a direct displacement SN2-like mechanism involving an …