title: 13C-NMR spectroscopy of keratan sulphates--assignments for five sialylated pentasaccharides derived from the non-reducing chain termini of bovine articular cartilage keratan sulphate by keratanase II digestion.
abstract: Skeletal keratan sulphate has been fragmented using the enzyme keratanase II, and 13C chemical-shift data are reported for five reduced sialylated pentasaccharides that derived from the non-reducing chain terminal region. They have the structures: NeuAc(alpha2-6)Gal(beta1-4)GlcNAc6S(beta1-3)Gal(beta1-4)GlcNAc6 S-ol, NeuAc(alpha2-3)Gal(beta1-4)GlcNAc6S(beta1-3)Gal(beta1-4)GlcNAc6 S-ol, NeuAc(alpha2-6)Gal(beta1-4)GlcNAc6S(beta1-3)Gal6S(beta1-4)++ +GlcNAc6S-ol, NeuAc(alpha2-3)Gal(beta1-4)GlcNAc6S(beta1-3)Gal(6S)(beta1-4)Glc NAc6S-ol, and NeuAc(alpha2-3)Gal(6S)(beta1-4)GlcNAc6S(beta1-3)Gal(6S)(beta1-4)++ +GlcNAc6S-ol, where GlcNAc6S-ol represents N-acetyl-glucosaminitol 6-O-sulphate and NeuAc represents N-acetylneuraminic acid. The use of these 13C-NMR spectroscopy data for the recognition of specific chain-capping structures within native keratan sulphates is discussed. In addition, examination of the data derived from the NeuAc(alpha2-6) capping structures strongly suggests that sulphation three residues away from the neuraminic acid cap has a profound effect upon the conformation of the capping region.
authors.affiliation: The Polymer Centre, School of Physics and Chemistry, Lancaster University, Bailrigg, England.
authors.forename: T N
authors.initials: TN
authors.lastname: Huckerby
authors.forename: G M
authors.initials: GM
authors.lastname: Brown
authors.forename: I A
authors.initials: IA
authors.lastname: Nieduszynski
mesh_terms: D000118:Acetylglucosaminidase / Q000378:metabolism*; D000818:Animals; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D002247:Carbon Isotopes; D002358:Cartilage, Articular / Q000737:chemistry*; D002417:Cattle; D007632:Keratan Sulfate / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism; D008969:Molecular Sequence Data; D019906:Nuclear Magnetic Resonance, Biomolecular; D009844:Oligosaccharides / Q000737:chemistry
chemical_list: D002247:Carbon Isotopes; D009844:Oligosaccharides; D007632:Keratan Sulfate; C086950:keratanase II; D000118:Acetylglucosaminidase