Isolation and characterization of the O-glycan chain of the human vitamin-D binding protein

Biochem Biophys Res Commun. 1983 Nov 30;117(1):324-31. doi: 10.1016/0006-291x(83)91579-6.


On a highly purified preparation, the structure of the carbohydrate chain of the human vitamin D-binding protein was investigated and two genetic forms of this protein were considered (Gc 2 and Gc 1 proteins). It was found that only the Gc 1 protein (Gc1a isoform) was glycosylated, the glycan moiety representing about 1% of the protein. The structure of this O-glycosidically linked glycan was determined to be: Neu Ac alpha (2 leads to 3) Gal beta (1 leads to 3) GaINAc alpha (1 leads to 0) Ser (or Thr). A tetrasaccharidic O-glycan with two N-acetylneuraminic residues was also characterized. The vitamin D-binding protein is a rare example of a serum protein O-glycosylated only on some genetic forms.

MeSH terms

  • Carrier Proteins / isolation & purification*
  • Electrophoresis, Polyacrylamide Gel
  • Gas Chromatography-Mass Spectrometry
  • Glycopeptides / analysis
  • Humans
  • Isoelectric Focusing
  • Polysaccharides / isolation & purification
  • Vitamin D-Binding Protein


  • Carrier Proteins
  • Glycopeptides
  • Polysaccharides
  • Vitamin D-Binding Protein