Engineering of hydrolysis reaction specificity in the transglycosylase cyclodextrin glycosyltransferase

Cyclodextrin glycosyltransferase (CGTase) is a member of the alpha-amylase family, a large group of enzymes that act on alpha-glycosidic bonds in starch and related compounds. Over twenty different reaction and product specificities have been found in this family. Although three-dimensional structure elucidation and the biochemical characterization of site-directed mutants have yielded a detailed insight into the mechanism of bond cleavage, the variation in reaction and product specificity is far from understood. This article gives an overview of recent developments in the understanding and engineering of transglycosylation and hydrolysis specificity in CGTase, which is one of the best-studied alpha-amylase family enzymes.