Takasaki S, Kobata A
Biochemistry. 1986 Sep 23;25(19):5709-15. doi: 10.1021/bi00367a054.
Asparagine-linked sugar chains were quantitatively released from fetuin by hydrazinolysis. Structural analysis of the sugar chains by sequential exoglycosidase digestion in combination with methylation analysis and Smith degradation revealed that most of them have typical biantennary (8%) and triantennary (74%) structures containing different amounts of N-acetylneuraminic acid residues. In addition, an unusual tetrasialyl triantennary sugar chain (17%) containing the Gal beta 1----3GlcNAc sequence in the outer chain moiety was detected, and its structure was elucidated as NeuAc alpha 2----3Gal beta 1----3(NeuAc alpha 2----6)-GlcNAc beta 1----4(NeuAc alpha 2----6Gal beta 1----4GlcNAc beta 1----2)Man alpha 1----3(NeuAc alpha 2----3Gal beta 1----4GlcNAc beta 1----2Man alpha 1----6)Man beta 1----4GlcNAc beta 1----4GlcNAc.
通过肼解从胎球蛋白中定量释放出天冬酰胺连接的糖链。通过外切糖苷酶顺序消化结合甲基化分析和史密斯降解对糖链进行结构分析，结果表明，大多数糖链具有典型的二天线（8%）和三天线（74%）结构，含有不同数量的N-乙酰神经氨酸残基。此外，还检测到一种不寻常的四唾液酸三天线糖链（17%），其外链部分含有Galβ1----3GlcNAc序列，其结构被阐明为NeuAcα2----3Galβ1----3(NeuAcα2----6)-GlcNAcβ1----4(NeuAcα2----6Galβ1----4GlcNAcβ1----2)Manα1----3(NeuAcα2----3Galβ1----4GlcNAcβ1----2Manα1----6)Manβ1----4GlcNAcβ1----4GlcNAc。
