蛋鸡输卵管碱性磷酸酶的提纯和性质

用硫酸铵沉淀、离子交换层析、亲和层析等方法将蛋鸡输卵管碱性磷酸酶提纯了113倍。等电聚焦电泳该酶出现1条带,PI为4.3,聚丙烯酰胺梯度凝胶电泳测得其分子量为127000,以磷酸苯二钠为底物,其Km值为4.76mmol/L,该酶对热稳定,对尿素敏感,对左旋咪唑不敏感,L-苯丙氨酸和L-色氨酸对该酶有较强的抑制作用,EDTA对该酶有一定程度的抑制作用,一定浓度的Mg2+、Mn2+、Zn2+、Ca2+、Cu2+、Co2+、Fe3+、Cd2+、Se4+对该酶均有不同程度的激活作用,除Mg2+和Mn+2外,高浓度的上述阳离子对该酶均有抑制作用。

Purification of Alkalinc Phosphatasc from Laying Hen Oviduct and Its Properties

Alkaline phosphatase of laying hen oviduct was purified 113-fold. Molecular weight of the enzyme is 127000, its isoelectric point is 4.3 and michelis constant is 4.76mmol/L. The enzyme has a stronger heat-resistance. It is sensitive to urea but insensitive to Levamisole. The enzyme is inhibited strongly by L-phenylalanine and L-tryptophan, and to some extent by EDTA. Mg2+ and Mn2+ strongly activate the enzyme and other metal ions may also activated it in varying degree at proper concentra-tion. It was found that the properties of laying hen oviduct alkaline phosphatase isoenzyme are similar to those of intestine alkaline phosphatase isoenzyme.