Novel multi-dimensional heteronuclear NMR techniques for the study of 13C-O-acetylated oligosaccharides: Expanding the dimensions for carbohydrate structures |
| |
Authors: | David N.M. Jones Brad Bendiak |
| |
Affiliation: | (1) Departments of Pharmacology, University of Colorado Health Sciences Center, Box C236, 4200 East Ninth Avenue, Denver, CO, 80262, U.S.A.;(2) Departments of Cellular and Structural Biology, University of Colorado Health Sciences Center, Box C236, 4200 East Ninth Avenue, Denver, CO, 80262, U.S.A. |
| |
Abstract: | Complex carbohydrates have critical roles in a wide variety of biological processes. An understanding of the molecular mechanisms that underlie these processes is essential in the development of novel oligosaccharide-based therapeutic strategies. Unfortunately, obtaining detailed structural information for larger oligosaccharides (>10 residues) can be exceedingly difficult, especially where the amount of sample available is limited. Here we demonstrate the application of 13 C O-acetylation in combination with novel NMR experiments to obtain much of the information required to characterize the primary structure of oligosaccharides. (H)CMeCOH-HEHAHA and H(CMe)COH-HEHAHA experiments are presented that use heteronuclear Hartmann–Hahn transfer to correlate the acetyl groups with sugar ring protons in peracetylated oligosaccharides. The in-phase, pure absorption nature of the correlation peaks in these experiments allows measurement of both chemical shifts and, importantly, 1H-1H coupling constants that are used to define the stereochemistry of the sugar ring. The (HCMe)COH and (HCMe)COH-RELAY experiments provide additional methods for obtaining chemical shift assignments for larger oligosaccharides to define the sites of glycosidic linkages from the patterns of acetylation. |
| |
Keywords: | C-13 labeling carbohydrates coupling constants heteronuclear Hartmann– Hahn O-acetylation oligosaccharides |
本文献已被 PubMed SpringerLink 等数据库收录! |
|