STRUCTURE AND ANTICOAGULANT ACTIVITY OF A FUCOSYLATED CHONDROITIN SULFATE FROM ECHINODERM - SULFATED FUCOSE BRANCHES ON THE POLYSACCHARIDE ACCOUNT FOR ITS HIGH ANTICOAGULANT ACTION
Pas. Mourao et al., STRUCTURE AND ANTICOAGULANT ACTIVITY OF A FUCOSYLATED CHONDROITIN SULFATE FROM ECHINODERM - SULFATED FUCOSE BRANCHES ON THE POLYSACCHARIDE ACCOUNT FOR ITS HIGH ANTICOAGULANT ACTION, The Journal of biological chemistry, 271(39), 1996, pp. 23973-23984
A polysaccharide isolated from the body wall of the sea cucumber Ludwi
gothurea grisea has a backbone like that of mammalian chondroitin sulf
ate: [4-beta-D-GlcA-1-->3-beta-D-GalNAc-1](n) but substituted at the 3
-position of the beta-D-glucuronic acid residues with sulfated alpha-L
-fucopyranosyl branches (Vieira, R. P., Mulloy, B., and Mourao, P. A.
S. (1991) J. Biol. Chem. 266, 13530-13536). Mild acid hydrolysis remov
es the sulfated alpha-L-fucose branches, and cleaved residues have bee
n characterized by H-1 NMR spectroscopy; the most abundant species is
fucose 4-O-monosulfate, but 2,4- and 3,4-di-O-sulfated residues are al
so present. Degradation of the remaining polysaccharide with chondroit
in ABC lyase shows that the sulfated alpha-L-fucose residues released
by mild acid hydrolysis are concentrated toward the non-reducing end o
f the polysaccharide chains; enzyme-resistant polysaccharide material
includes the reducing terminal and carries acid resistant L-fucose sub
stitution. The sulfated alpha-L-fucose branches confer anticoagulant a
ctivity on the polysaccharide. The specific activity of fucosylated ch
ondroitin sulfate in the activated partial thromboplastin time assay i
s greater than that of a linear homopolymeric alpha-L-fucan with about
the same level of sulfation; this activity is lost on defucosylation
or desulfation but not on carboxyl-reduction of the polymer. Assays wi
th purified reagents show that the fucosylated chondroitin sulfate can
potentiate the thrombin inhibition activity of both antithrombin and
heparin cofactor II.