鸭肝蛋白酶的分离纯化及其部分性质研究  

A Study of the Isolation and Purification of Duck (Anas platyrhynchos) Liver Protease and of Its Properties

作　　者：岑亮[1] 张丽丽[1] 邱慧[1] 郭小路[1] 唐云明[1] 

机构地区：[1]西南大学生命科学学院,重庆400715

出　　处：《西南大学学报（自然科学版）》2007年第2期97-101,共5页Journal of Southwest University(Natural Science Edition)

基　　金：重庆市科委资助项目(CSTC;2004AC1012)

摘　　要：经Tris-HCl缓冲液抽提、硫酸铵分级沉淀、DEAE-Sepharose Fast Flow离子交换层析、Sephacryl S-200凝胶过滤层析,得到鸭肝蛋白酶电泳纯制品.纯化倍数为650·16倍,回收率为19·23%.经SDS-PAGE和凝胶过滤测得该酶的分子量为35kD.该酶在pH6·0～11·0,温度低于25℃稳定,当温度上升到55℃时活性迅速下降.该酶在pH10和60℃时达到最高活性.进一步研究得知:Cu2+离子对该酶有明显促进作用,而Mn2+却使酶几乎失活.以酪蛋白为底物,在pH10·0、37℃时测得米氏常数Km值为1·33%.A protease was purified from Anas platyrhynchos. The protease extraction was prepared through homogenization and centrifugation by Tris-HCl buffer at 4 ℃. The supernatant was purified by ammonium sulfate grading precipitation and the active component was dialyzed and concentrated. Then, the protease was purified by means of DEAE-Sepharose Fast Flow anion-exchange chromatography and Sephacryl S-200 chromatography. The purity of the purified protease was confirmed by the presence of a single band on SDS-PAGE. Sephacryl S-200 chromatography and SDS-PAGE showed that the molecular weight of this protease is 35 kD. The enzyme appeared stable at pH 6.0～11.0 and temperature below 25 ℃. When the temperature rose above 55 ℃, a rapid decline of its stability occurred. The enzyme showed maximum activity at pH 10. 0 and 60 ℃. Cu^2＋ activated the enzyme and Mn^2＋ inactivated it. Using casein as the substrate, the Km value of enzyme was estimated to be 1.33% at pH 10. 0, 37 ℃.

关 键 词：鸭 肝脏 蛋白酶 分离纯化 性质 

分 类 号：Q959.482[生物学—动物学]