Galactosyltransferase acceptor specificity of the lactose synthetase A protein.
Galactosyltransferase acceptor specificity of the lactose synthetase A protein.
复制标题
乳糖合成酶 A 蛋白的半乳糖基转移酶受体特异性。
DOI：
10.1016/s0021-9258(18)62817-0
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发表时间：
1970
期刊：
影响因子：
--
通讯作者：
K. Ebner
中科院分区：
文献类型：
--
作者：
F. Schanbacher;K. Ebner
在不存在和存在α-乳白蛋白的情况下，检测了从牛乳中分离的高度纯化的A蛋白（半乳糖基转移酶）的半乳糖基受体特异性。α-乳清蛋白抑制半乳糖向N-乙酰葡糖胺的转移，但不会明显抑制向N-乙酰葡糖胺和其他β-1，4-连接糖苷（如纤维二糖、纤维二糖（葡糖基-β-1，4-果糖）、β-d-甲基葡萄糖、葡糖基-β-1，4-甘露糖、吲哚基-β-d-葡萄糖和卵清蛋白）的低聚物的转移。α-糖苷类在α-乳白蛋白存在下是不良底物，但在α-乳白蛋白不存在下不是底物。乳糖的生物合成和糖蛋白的碳水化合物侧链中Gal-β-1，4-GlcNAc键的形成是相容的，并且通过相同的半乳糖基转移酶进行。
The galactosyl acceptor specificity of the highly purified A protein (galactosyltransferase) isolated from bovine milk was examined in the absence and presence of α-lactalbumin. α-Lactalbumin inhibits the transfer of galactose toN-acetylglucosamine but does not appreciably inhibit the transfer to oligomers ofN-acetylglucosamine and other β-1,4 linked glycosides such as cellobiose, cellobiulose (glucosyl-β-1,4-fructose), β-d-methylglucose, glucosyl-β-1,4-mannose, indoxyl-β-d-glucose, and ovalbumin. α-Glycosides are poor substrates in the presence of α-lactalbumin but are not substrates in its absence. The biosynthesis of lactose and the formulation of the Gal-β-1,4-GlcNAc linkage in the carbohydrate side chain of glycoproteins are compatible and are carried out by the same galactosyltransferase.