Chemical structure of antithrombin-active Rhamnan sulfate from Monostrom nitidum.
Rhamnan sulfate was extracted with boiling water from the cell wall of Monostroma nitridum, and the resulting extract was purified by ion-exchange and size-exclusion chromatography. The polysaccharide, which is regarded as a homopolysaccharide, was 6-fold more antithrombin-active than the heparin standard. The antithrombin activity was decreased, by desulfation, although the non-active product still retained 8% of the sulfate ester. A comparative structural study of the intact rhamnan sulfate and rhamnan, its desulfated product, by periodate oxidation, Smith degradation and methylation analysis revealed the rhamnan sulfate to consist of alpha-1,3-linked L-rhamnose residues, some of which were substituted with sulfate groups mainly at position O-2. Minor amounts of internal 1,2-linked rhamnose and branched rhamnose linkages were also detected.
Harada
N
N
Department of Biochemistry, Saitama University Urawa, Japan.
Maeda
M
M
D002240:Carbohydrate Sequence; D003837:Deoxy Sugars / Q000737:chemistry*; D056890:Eukaryota / Q000737:chemistry*; D008351:Mannans / Q000737:chemistry*; D008969:Molecular Sequence Data; D013431:Sulfates / Q000737:chemistry; D013917:Thrombin / Q000037:antagonists & inhibitors*
D003837:Deoxy Sugars; D008351:Mannans; D013431:Sulfates; C065836:rhamnan; D013917:Thrombin