title: Skeletal keratan sulphate chains isolated from bovine intervertebral disc may terminate in alpha(2----6)-linked N-acetylneuraminic acid.
abstract: Peptido-keratan sulphate fragments were isolated from the nucleus pulposus of bovine intervertebral discs (2-year-old animals) after digestion with chondroitin ABC lyase followed by digestion with diphenylcarbamoyl chloride-treated trypsin of A1D1 proteoglycans and gel-permeation chromatography on Sepharose CL-6B. The peptido-keratan sulphate fragments were subjected to alkaline borohydride reduction. The reduced chains were treated with keratanase in the presence of the sialidase inhibitor 2,3-dehydro-2-deoxy-N-acetylneuraminic acid, and the digest was subjected to alkaline borohydride reduction. This produced oligosaccharides with galactitol at their reducing ends. This reduced digest was chromatographed on a Nucleosil 5 SB anion-exchange column and individual oligosaccharides were isolated. One of these was shown by 600 MHz 1H-n.m.r. spectroscopy to have the following structure: NeuAc alpha 2-6Gal beta 1-4GlcNAc(6-SO4)beta 1-3Gal-ol The structure of this oligosaccharide shows that keratan sulphate chains from bovine intervertebral disc have non-reducing termini with N-acetylneuraminic acid linked alpha(2----6) as well as alpha(2----3) to an unsulphated galactose.
authors.affiliation: Division of Biological Sciences, Lancaster University, Bailrigg, U.K.
authors.forename: J M
authors.initials: JM
authors.lastname: Dickenson
authors.forename: T N
authors.initials: TN
authors.lastname: Huckerby
authors.forename: I A
authors.initials: IA
authors.lastname: Nieduszynski
mesh_terms: D000818:Animals; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D002417:Cattle; D002851:Chromatography, High Pressure Liquid; D006026:Glycoside Hydrolases; D007202:Indicators and Reagents; D007403:Intervertebral Disc / Q000737:chemistry*; D007632:Keratan Sulfate / Q000737:chemistry* / Q000302:isolation & purification; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000737:chemistry* / Q000302:isolation & purification; D011509:Proteoglycans / Q000302:isolation & purification; D001616:beta-Galactosidase
chemical_list: D007202:Indicators and Reagents; D009844:Oligosaccharides; D011509:Proteoglycans; D007632:Keratan Sulfate; D006026:Glycoside Hydrolases; C026093:keratan-sulfate endo-1,4-beta-galactosidase; D001616:beta-Galactosidase