摘要
通过ε-氨基己酸的解离作用,利用CM Sepharose Fast Flow凝胶过滤层析、Lysine-Sepharose(赖氨酸-琼脂糖凝胶)亲和层析的方法,通过SDS-聚丙烯酰胺凝胶电泳纯度鉴定,从末乳中分离出一种具有纤溶活性的碱性蛋白酶。采用凝胶色谱和等电聚焦法对其分子量和等电点进行测定。结果表明:该蛋白酶为单体蛋白,纯化倍数2.11,分子量为47.0 ku,等电点7.8。纯化后酶的活性可完全被PMSF抑制剂抑制,属于丝氨酸蛋白酶家族。对酪蛋白具有一定的水解能力。
One alkaline protease with plasmin activity was isolated from late-lactation bovine milk. The enzyme was purified to electrophoretic homogeneity using 6-Amino caproic acid, CM Sepharose Fast Flow ion exchange chromatography, Lysine-Sepharose affinity chromatogra- phy. Purify multiple is 2.11. The isoeleetrie point of protease was 7.8. The molecular weight was 47.0 ku measured by SDS-PAGE. Activity of protease was completely inhibited by the serine protease inhibitor, PMSF, indicated that it belongs to the serine protease family. The en- zyme had a high degrading activity for casein.
出处
《中国乳品工业》
CAS
北大核心
2012年第6期22-25,共4页
China Dairy Industry
关键词
末乳
碱性蛋白酶
纤溶活性
late-lactation milk
alkalineProtease
plasmin activity
