Structural analysis of glycosaminoglycan component of bikunin

CARB 94

Lianli Chi, chil@rpi.edu1, Toshihiko Toida2, and Robert J. Linhardt, linhar@rpi.edu1. (1) Department of Chemistry and Chemical Biology, Rensselaer Polytechnic Institute, 110 8TH ST, Troy, NY 12180, (2) Faculty of Pharmaceutical Sciences, Chiba University, 1-33, Yayoi, Inage-ku, Chiba, 263-8522, Japan
Bikunin is a proteoglycan that acts as a trypsin inhibitor in human plasma and can be isolated from urine. A single chondroitin sulfate chain is covalently attached to a core protein in bikunin. While the sequence of the core protein is known, the structure and sequence of this chondroitin sulfate chain has not been determined. The chondroitin sulfate component from bikunin was removed from the core protein through beta elimination and recovered using a strong-anion exchange spin column. The structure of this chondroitin sulfate chain was analyzed using NMR and polyacrylamide gel electrophoresis. Chondroitin lyase was used to break down the chondroitin sulfate into oligosaccharides and disaccharides that were then determined by mass spectrometry.