Molecular distinctions between heparan sulphate and heparin. Analysis of sulphation patterns indicates that heparan sulphate and heparin are separate families of N-sulphated polysaccharides.

摘要: Heparan sulphate and heparin are chemically related alpha beta-linked glycosaminoglycans composed of alternating sequences glucosamine uronic acid. The amino sugars may be N-acetylated or N-sulphated, the latter substituent is unique to these two polysaccharides. Although there general agreement that heparan usually less sulphated than heparin, reproducible differences in their molecular structure have been difficult identify. We suggest this because most analytical data obtained with degraded materials not necessarily representative complete polysaccharide chains. In present study intact sulphates, labelled biosynthetically [3H]glucosamine Na2(35)SO4, were isolated from surface membranes several types cells culture. was analysed by HNO2 hydrolysis followed fractionation products gel filtration high-voltage electrophoresis. Results showed all sulphates approximately equal numbers N-sulpho N-acetyl substituents, arranged a similar, predominantly segregated, manner along chain. O-Sulphate groups close proximity N-sulphate but, unlike latter, number O-sulphate could vary considerably different cellular origins ranging 20 75 per 100 disaccharide units. Inspection published on frequency very high (greater 80% residues N-sulphated) concentration exceeded groups. conclude other observations separate families N-sulphated glycosaminoglycans.