title: alpha 2-8 Sialic acid polymers: size, structure, and compositional analysis.
abstract: A series of three variable assay procedures is described to provide overlapping information on the size, structure, and composition of the alpha 2-8 linked polysialic acid chains present on a wide variety of critical cell surface glycoproteins. Technical advances in instrumentation have permitted the development of new applications for a methodology involving the sequential use of periodate and borohydride to modify terminal sialic acid residues. The procedures described here provide a rapid and facile assay for (a) the determination of polysialic acid chain length, (b) the simultaneous identification of N-acetylneuraminic acid, N-glycolyneuraminic acid, and KDN (deaminated sialic acid) when present in a single preparation, (c) the ability to distinguish qualitatively between reducing and nonreducing polymers, and (d) the ability to determine the number of chains bound to a glycoprotein of known molecular weight.
authors.affiliation: National Institute of Diabetes, Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892.
authors.forename: G
authors.initials: G
authors.lastname: Ashwell
authors.forename: W K
authors.initials: WK
authors.lastname: Berlin
authors.forename: O
authors.initials: O
authors.lastname: Gabriel
mesh_terms: D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D008969:Molecular Sequence Data; D015394:Molecular Structure; D008970:Molecular Weight; D019158:N-Acetylneuraminic Acid; D010084:Oxidation-Reduction; D011108:Polymers / Q000737:chemistry*; D012680:Sensitivity and Specificity; D012794:Sialic Acids / Q000737:chemistry*
chemical_list: D011108:Polymers; D012794:Sialic Acids; D019158:N-Acetylneuraminic Acid