Structures of the asparagine-linked sugar chain of glucose transporter from human erythrocytes.
The asparagine-linked sugar chain of glucose transporter from human erythrocytes was quantitatively released as oligosaccharides from the polypeptide backbone by hydrazinolysis. They were converted to radioactive oligosaccharides by NaB3H4 reduction after N-acetylation and fractionated by anion-exchange column chromatography and Bio-Gel P-4 column chromatography after sialidase treatment. Structural study of each oligosaccharide by exo- and endoglycosidase digestion and methylation analysis indicated that the glycoprotein contains a high-mannose-type oligosaccharide, Man9.GlcNAc.GlcNAc, and biantennary complex-type oligosaccharides with Man alpha 1----6(+/- GlcNAc beta 1----4)(Man alpha 1----3) Man beta beta 1----4GlcNAc beta 1----4(+/- Fuc alpha 1----6)GlcNAc as their cores and the poly-N-acetyllactosamine composed of about 16 N-acetyllactosaminyl units as their outer chains. These structural features of the sugar moiety of glucose transporter are quite different from those of two major intrinsic glycoproteins of human erythrocytes, glycophorin A and band 3.
Endo
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Department of Biochemistry, University of Tokyo, Japan.
Kasahara
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M
Kobata
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A
D000606:Amino Sugars / Q000737:chemistry*; D001216:Asparagine; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D002852:Chromatography, Ion Exchange; D004912:Erythrocytes / Q000737:chemistry*; D006021:Glycophorins / Q000737:chemistry*; D006026:Glycoside Hydrolases; D006801:Humans; D008969:Molecular Sequence Data; D009004:Monosaccharide Transport Proteins / Q000737:chemistry*; D009844:Oligosaccharides
D000606:Amino Sugars; D006021:Glycophorins; D009004:Monosaccharide Transport Proteins; D009844:Oligosaccharides; D001216:Asparagine; D006026:Glycoside Hydrolases