1986 年 99 巻 1 号 p. 55-62
γ-Glutamyltranspeptidase purified from human kidneys contains 4-5 asparaginelinked sugar chains in each molecule. The sugar chains were released from the polypeptide portion of the enzyme by hydrazinolysis as oligosaccharides and separated by paper electrophoresis into one neutral and two acidic fractions. By sequential exoglycosidase digestion and methylation analysis, the neutral fraction, which comprised 69% of total oligosaccharides, was shown to be a mixture of bisected bi and triantennary complex-type sugar chains with and without a fucose on the proximal N-acetylglucosamine residue and with Galβ1→4GlcNAc and/or Galβ1→4(Fucαl→3)G1cNAc groups in their outer chain moieties. The acidic oligosaccharide fractions were mixtures of mono and disialyl derivatives of bisected triantennary complex-type oligosaccharides with Galβ1 →4G1cNAc and/or Galβ1→4 (Fucα1→3) GlcNAc group in their outer chain moieties. Some of the outer chains of the acidic oligosaccharides were considered to be sialylated X-antigenic structures.
