Chapter 7 - Carbohydrate Structure and Dynamics from NMR

Abstract

High resolution nuclear magnetic resonance (NMR) spectroscopy is a powerful method for the analysis of carbohydrates. Methods for determination of composition, sequence, conformation, and dynamics of oligosaccharides and glyco-conjugates are reviewed here. Recent innovations, such as selective excitation, three-dimensional pulse sequences, and gradients are illustrated with numerous examples from the literature. The importance of carbohydrates in biology is gaining increasing recognition. Carbohydrates are involved in a diverse array of processes involving cell recognition, including cell adhesion, clearance of circulating glycoproteins, binding of antibodies, pathogen, toxins, lymphocyte homing, and differentiation. New structures occurring on glycoproteins and proteoglycans are being reported continually. Assignment leads to identification of the sequence of residues in an oligosaccharide, but NMR may not be the most efficient method for primary sequencing. However, NMR is a powerful method for determining the solution conformation of oligosaccharides under physiological conditions, and for studying their interactions with other molecules. NMR may be the only method available to study these aspects, if the system of interest will not crystallize. It is hoped that this chapter has demonstrated that the increasing recognition of the important and diverse functions of carbohydrates, in combination with the technical advances described herein, is leading to even more rapid progress in the understanding of this class of biomolecules.