360-MHz 1H nuclear-magnetic-resonance spectroscopy of sialyl-oligosaccharides from patients with sialidosis (mucolipidosis I and II).
360-MHz proton nuclear magnetic resonance spectra were recorded of 10 sialyl-oligosaccharides isolated from urine of sialidosis patients. Their structures are related to the complex asparagine-linked glycan chains of glycoproteins. By correlation of these spectra and comparison with spectra of reference glycopeptides and sialyl-lactose isomers it was possible to assign all signals belonging to anomeric, mannose H-2, sialic acid H-3 and N-acetyl protons. The number of the consituting monosaccharide residues of the oligomers can be obtained by integration of the above-mentioned signals. The chemical shifts of the anomeric and mannose H-2 protons give information about the type of glycan structure (mono-, bi-, triantennary) and the presence of terminal sialic acid at each of the antennas. The chemical shifts of sialic acid H-3 protons are typical for sialic acid residues in 2 leads to 3 or 2 leads to 6 linkage to galactose.
D002241:Carbohydrates / Q000032:analysis; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D008968:Molecular Conformation; D009081:Mucolipidoses / Q000652:urine*; D009844:Oligosaccharides / Q000652:urine; D012794:Sialic Acids
D002241:Carbohydrates; D009844:Oligosaccharides; D012794:Sialic Acids