Yoshima H, Mizuochi T, Ishii M, Kobata A
Cancer Res. 1980 Nov;40(11):4276-81.
alpha-Fetoprotein purified from human serum was found to contain an asparagine-linked sugar chain in one molecule. The sugar chain was quantitatively released from the polypeptide moiety by hydrazinolysis and recovered as oligosaccharides after N-acetylation. The oligosaccharide mixture was separated into a neutral (N) and two acidic (A-1 and A-2) fractions by paper electrophoresis. By combination of sequential exoglycosidase digestion, methylation analysis, and concanavalin A-Sepharose column chromatography, the structures of these fractions were determined to be: Gal beta 1 leads to 4GlcNAc beta 1 leads to 2Man alpha 1 leads to 6(Gal beta 1 leads to 4GlcNAc beta 1 leads to 2Man alpha 1 leads to 3)Man beta 1 leads to 4GLcNAc beta 1 leads to 4(+/- Fuc alpha 1 leads to 6)GlcNAc; Gal beta 1 leads to 4GlcNAc beta 1 leads to 2Man alpha 1 leads to 6(NeuAc alpha 2 leads to 6Gal beta 1 leads to 4GlcNAc beta 1 leads to 2Man alpha 1 leads to 3)Man beta 1 leads to 4GlcNAc beta 1 leads to 4(+/- Fuc alpha 1 leads to 6(GlcNAc; and NeuAc alpha 2 leads to 6Gal beta 1 leads to 4GlcNAc beta 1 leads to 2Man alpha 1 leads to 6(NeuAc alpha 2 leads to 6Gal beta 1 leads to 4GlcNAc beta 1 leads to 2Man alpha 1 leads to 3)Man beta 1 leads to 4GlcNAc beta 1 leads to 4(+/- Fuc alpha 1 leads to 6)GlcNAc.
从人血清中纯化的甲胎蛋白被发现一个分子中含有一条天冬酰胺连接的糖链。通过肼解作用，糖链从多肽部分定量释放，并在N-乙酰化后作为寡糖回收。通过纸电泳将寡糖混合物分离为一个中性（N）部分和两个酸性（A-1和A-2）部分。通过顺序外切糖苷酶消化、甲基化分析和伴刀豆球蛋白A-琼脂糖柱色谱法相结合，确定这些部分的结构为：Galβ1→4GlcNAcβ1→2Manα1→6（Galβ1→4GlcNAcβ1→2Manα1→3）Manβ1→4GlcNAcβ1→4（±Fucα1→6）GlcNAc；Galβ1→4GlcNAcβ1→2Manα1→6（NeuAcα2→6Galβ1→4GlcNAcβ1→2Manα1→3）Manβ1→4GlcNAcβ1→4（±Fucα1→6）GlcNAc；以及NeuAcα2→6Galβ1→4GlcNAcβ1→2Manα1→6（NeuAcα2→6Galβ1→4GlcNAcβ1→2Manα1→3）Manβ1→4GlcNAcβ1→4（±Fucα1→6）GlcNAc。
