Non-natural oligosaccharides can be expected to exhibit new functions and applications in glycoscience such as potential as drug candidates. Enzymatic glycosylation is a useful tool for the preparation of oligosaccharides with well-defined structure. The a-(1?4)-glucan chains can be constructed by phosphorylase-catalyzed successive enzymatic a-glucosylations using a-D-glucose 1-phosphate (Glc-1-P) as a glycosyl donor and maltooligosaccharides as a glycosyl acceptor. Since enzymes often express loose specificity for recognition of substrate structures, extension of the phosphorylase-catalyzed glycosylations using analogue substrates of Glc-1-P are an efficient approach to obtain new non-natural oligosaccharides. On the basis of above viewpoints, this presentation reports the enzymatic synthesis of chitin/chitosan stereoisomers, non-natural saccharides, by thermostable phosphorylase-catalyzed a-glucosaminylation using a-D-glucosamine 1-phosphate (GlcN-1-P) as a glycosyl donor. Consequently, it was found that this enzyme catalyzed successive a-glucosaminylations to give a chain of a-(1?4)-D-glucosamine units. Furthermore, N-acetylation of the product gave a-(1?4)-linked N-acetyl-D-glucosamine chain. The structures of these materials correspond to the chitin/chitosan stereoisomers. 

Enzymatic synthesis of chitin/chitosan stereoisomers by thermostable phosphorylase catalysis

248th National Meeting (2014)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.