alpha 2-8 Sialic acid polymers: size, structure, and compositional analysis.

G Ashwell; W K Berlin; O Gabriel

doi:10.1006/abio.1994.1523

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alpha 2-8 Sialic acid polymers: size, structure, and compositional analysis.

G Ashwell·W K Berlin·O Gabriel

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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.

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Carbohydrate Conformation Carbohydrate Sequence Molecular Sequence Data Molecular Structure Molecular Weight N-Acetylneuraminic Acid Oxidation-Reduction Polymers Sensitivity and Specificity Sialic Acids Journal Article

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G Ashwell, W K Berlin, O Gabriel. 1994-11-01. alpha 2-8 Sialic acid polymers: size, structure, and compositional analysis.. https://doi.org/10.1006/abio.1994.1523

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