title: Structure determination of oligosaccharides isolated from Cad erythrocyte membranes by permethylation analysis and 500-MHz 1H-NMR spectroscopy.
abstract: Alkaline borohydride reductive cleavage (beta-elimination) of glycophorin A isolated from one individual of the rare blood group Cad, resulted in the release of six acidic oligosaccharide-alditols which were separated by high-performance liquid chromatography (HPLC) on an alkyl amine silicagel column. The structure of four of them has been determined by the application of methanolysis, methylation analysis and 1H-NMR spectroscopy at 500 MHz. The structures and relative amounts were as follows: oligosaccharide 1: NeuAc(alpha 2-3)Gal(beta 1-3)GalNAc-ol (3.5%); oligosaccharide 3: GalNAc(beta 1-4)[NeuAc(alpha 2-3)]Gal(beta 1-3)GalNAc-ol (10.5%); oligosaccharide 5: NeuAc(alpha 2-3)Gal(beta 1-3)[NeuAc(alpha 2-6)]GalNAc-ol (10.4%); oligosaccharide 6: GalNAc(beta 1-4)[NeuAc(alpha 2-3)]Gal(beta 1-3)[NeuAc(alpha 2-6)]GalNAc-ol (71.2%). The two other oligosaccharides (2 and 4) were obtained in very low amount. The major pentasaccharide (oligosaccharide 6) carries the blood group Cad determinant and is a potent inhibitor of human anti-Sda antibody.
mesh_terms: D001789:Blood Group Antigens; D055598:Chemical Phenomena; D002621:Chemistry; D002851:Chromatography, High Pressure Liquid; D004910:Erythrocyte Membrane / Q000032:analysis*; D006021:Glycophorins / Q000302:isolation & purification; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D008745:Methylation; D009844:Oligosaccharides / Q000097:blood / Q000302:isolation & purification*
chemical_list: D001789:Blood Group Antigens; D006021:Glycophorins; D009844:Oligosaccharides