Engineering of Hydrolysis Reaction Specificity in the Transglycosylase Cyclodextrin Glycosyltransferase
نویسنده
چکیده
Cyclodextrin glycosyltransferase (CGTase) is a member of the a-amylase family, a large group of enzymes that act on a-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 a-amylase family enzymes.
منابع مشابه
Engineering of cyclodextrin product specificity and pH optima of the thermostable cyclodextrin glycosyltransferase from Thermoanaerobacterium thermosulfurigenes EM1.
The product specificity and pH optimum of the thermostable cyclodextrin glycosyltransferase (CGTase) from Thermoanaerobacterium thermosulfurigenes EM1 was engineered using a combination of x-ray crystallography and site-directed mutagenesis. Previously, a crystal soaking experiment with the Bacillus circulans strain 251 beta-CGTase had revealed a maltononaose inhibitor bound to the enzyme in an...
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The enzymes from the alpha-amylase family all share a similar alpha-retaining catalytic mechanism but can have different reaction and product specificities. One family member, cyclodextrin glycosyltransferase (CGTase), has an uncommonly high transglycosylation activity and is able to form cyclodextrins. We have determined the 2.0 and 2.5 A X-ray structures of E257A/D229A CGTase in complex with ...
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Cyclodextrin glycosyltransferase (CGTase) (EC 2.4.1.19) is used for the industrial production of cyclodextrins. Its application, however, is hampered by the limited cyclodextrin product specificity and the strong inhibitory effect of cyclodextrins on CGTase activity. Recent structural studies have identified Arg47 in the Bacillus circulans strain 251 CGTase as an active-site residue interacting...
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