Deaminated neuraminic acid-rich glycoprotein of rainbow trout egg vitelline envelope. Occurrence of a novel alpha-2,8-linked oligo(deaminated neuraminic acid) structure in O-linked glycan chains.
Deaminated neuraminic acid-rich glycoprotein (KDN-gp), first found and isolated from the vitelline envelope of rainbow trout eggs (Inoue, S., Kanamori, A., Kitajima, K., and Inoue, Y. (1988) Biochem. Biophys. Res. Commun. 153, 172-176), has been found to contain a number of O-linked glycan. Oligosaccharides were released by alkaline borohydride treatment of KDN-gp. Following fractionation by DEAE-Sephadex A-25 and thin-layer chromatography, a series of acidic oligosaccharides were obtained and analyzed for their chemical structures. The structure is based on composition analysis, methylation analysis, alkali-catalyzed "peeling" reactions, periodate oxidation, 400-MHz one- and two-dimensional 1H NMR spectroscopy, and molecular secondary ion mass spectrometry. The O-linked oligosaccharides isolated from KDN-gp have been shown to contain a common core trisaccharide Gal beta 1-3GalNAc alpha 1-3GalNAc in which the terminal Gal residue is blocked by a single residue of deaminated neuraminic acid (KDN) and the proximal GalNAc residue is substituted by alpha-2,8-linked oligo(KDN) chains. Structures of KDN-oligosaccharide chains in the glycoprotein are novel and expressed by the following general formula, where n = 0-5, for which data are available. [formula: see text]
Kanamori
A
A
Department of Biophysics and Biochemistry, Faculty of Science, University of Tokyo, Japan.
Inoue
S
S
Iwasaki
M
M
Kitajima
K
K
Kawai
G
G
Yokoyama
S
S
Inoue
Y
Y
D000818:Animals; D002240:Carbohydrate Sequence; D002855:Chromatography, Thin Layer; D004527:Egg Proteins / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D012794:Sialic Acids / Q000737:chemistry*; D012795:Sialoglycoproteins / Q000737:chemistry*; D014337:Trout; D014817:Vitelline Membrane / Q000737:chemistry*
D004527:Egg Proteins; D012794:Sialic Acids; D012795:Sialoglycoproteins