STRUCTURE OF FUCOSE BRANCHES IN THE GLYCOSAMINOGLYCAN FROM THE BODY-WALL OF THE SEA-CUCUMBER STICHOPUS-JAPONICUS

Fucose-branched chondroitin sulfate E was prepared from the body wall of sea cucumber Stichopus japonicus. The purified glycosaminoglycan (G AG) was chemically desulfated, followed by carboxyl reduction. Intact, desulfated, and desulfated/carboxyl-reduced GAG fractions were subjec ted to per-O-methylation. GC-MS analyses of the resultant partially me thylated alditol acetates demonstrated that the fucose branch is forme d by two fucopyranosyl residues linked glycosidically through position (1 --> 3), and that the fucose branch and glucuronic acid are almost equimolar. In addition, it was elucidated that about 20% of the branch es stretch from O-3 position of a glucuronic acid moiety of the core c hondroitin sulfate polymer, while remaining fucose branches are postul ated to protrude from O-4 and/or O-6 position(s) of a N-acetylgalactos amine moiety. This fucose branch was also confirmed to be highly sulfa ted according to six kinds of substitution pattern in methylation anal ysis. [GRAPHICS] (C) 1997 Elsevier Science Ltd.