Structure and effect of sulfated fucose branches on anticoagulant activity of the fucosylated chondroitin sulfate from sea cucumber Thelenata ananas

Fucosylated chondroitin sulfate (FuCS) is a glycosaminoglycan from sea cucumber, made up of alternating β-d-glucuronic acid and N-acetyl-β-d-galactosamine units. The β-d-glucuronic acid residues have branches of sulfated fucose, while the fucose branches may have distinguishable patterns and proportions of sulfate substitution. The structure of the sulfated fucose branches of the fucosylated chondroitin sulfate from the sea cucumber Thelenata ananas has been characterized by mild acid hydrolysis and NMR technology. The results showed that the fucose residues are made up of 3-,4-mono-O-sulfated fucose and 2,4-di-O-sulfated fucose with about 25:22:53, respectively. The sulfated fucose branches are essential for the anticoagulant action of FuCS, and this potent effect is possibly related to the occurrence of 2,4-di-O-sulfated fucose units. Furthermore, these branches could constitute the structural requirement for the binding of the glycosaminoglycan to coagulant enzymes, such as thrombin by HCII, factor X by the intrinsic tenase complex.