Directed evolution of glycosyltransferases for the enzymatic synthesis of novel oligosaccharides

Abstract

Glycosyltransferases, the enzymes that are responsible for the synthesis of the vast majority of oligosaccharides in the biosphere, are an attractive alternative to chemical approaches for the synthesis of complex oligosaccharides. My proposed research is to use directed evolution methodologies in order to engineer glycosyltransferases for the enzymatic synthesis of novel oligosaccharides. More specifically, I plan to evolve bacterial glycosyltransferases, to utilize readily synthesized and inexpensive glycosyl fluorides as donor sugars for transfer to a range of different glycosyl acceptors. In addition I propose to change the selectivity of the glycosyltransferases to accommodate different sugar acceptors and open the possibility of enzymatically synthesizing novel oligosaccharides. The engineered enzymes will shed light on the mechanisms of glycosyltransferases and the oligosaccharide products may be of value in the search for new therapeutic agents. The fellowship experience will give me the opportunity to conduct research in the large and important field of carbohydrate processing enzymes, which will be different from my previous research experience where I never dealt with carbohydrates or glycosyltransferases. I will be exposed, during the fellowship period, to a variety of ideas and techniques that are unique to the glycobiology world and this will enhance my professional growth, eventually as an independent investigator conducting research in this important field.