Evidence for uniformity of the carbohydrate chains in individual glycoprotein molecular variants

Pooled and alkylated α₁-acid glycoprotein was fractionated on a Con A-Sepharose column into two fractions : Con A-non reactive and Con A-reactive. The carbohydrate moiety from the α₁-acid glycoprotein Con A-reactive variant, obtained by hydrazinolysis and quantitative re-N-acetylation, contains only identical two-branched oligosaccharide chains. From the present work on α₁-acid glycoprotein and from previous studies on α₁-fetoprotein, one can assume that glycoprotein glycosylation occurs uniformly along each polypeptide chain giving it identical oligosaccharide units at each glycosylation site.