NMR approaches to glycosyltransferase structure and interactions

CARB 10

James H. Prestegard, jpresteg@ccrc.uga.edu, Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens, GA 30602
Glycosyltransferases are a key element in building the complex cell surface carbohydrates that mediate so much of a cell's interaction with its environment. Aberrant activity has in several cases been linked to diseases such as cancer and diabetes, making an understanding of glycosyltransferse structure and interaction with substrates an important step in combating disease. However, structural characterization has been challenging. Here we describe new NMR approaches to this characterization. Structure can be approached with data from isotopic labels on specific amino acids, providing resonances from these sites can be assigned. A new strategy that links sequence information from mass spectrometry with NMR resonance positions promises to provide this assignment information. Given assignments, data from residual dipolar couplings and nitroxide enhanced spin relaxation is beginning to provide structural information on active site location and interaction with substrates. We will report progress using these methods on glycosyltransferases GnTV and ST6Gal I.