title: Assignment of the 1H-n.m.r. spectra of heparin and heparan sulphate.
abstract: Resonances from the main repeating unit of heparan, ----4)-beta-D-GlcA-(1----4)-alpha-D-GlcNAc-(1----, have been assigned by using a sample of the capsular polysaccharide of E. coli K5. Comparison of the spectra of heparan sulphate samples before and after O- and/or N-desulphation, with re-N-acetylation or re-N-sulphation, allowed assignment of some of the H-1 doublets in terms of sequence effects. Chemical shifts for H-1 of unsulphated uronic acid residues are influenced by 6-sulphation of the nearest neighbour GlcN on the reducing side; those of GlcN residues vary according to whether they have IdoA or GlcA as the nearest neighbour on the reducing side. The H-1 doublets due to residues in the binding sequence for antithrombin have been assigned by comparison of the spectra of heparins having high and low affinities for immobilised antithrombin.
mesh_terms: D000818:Animals; D000991:Antithrombins; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D002417:Cattle; D004926:Escherichia coli; D006025:Glycosaminoglycans; D006493:Heparin; D006497:Heparan Sulfate; D006859:Hydrogen; D007413:Intestinal Mucosa; D008168:Lung; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D011135:Polysaccharides, Bacterial; D013552:Swine
chemical_list: D000991:Antithrombins; D006025:Glycosaminoglycans; D006493:Heparin; D006497:Heparan Sulfate; D006859:Hydrogen; D011135:Polysaccharides, Bacterial