重组E.coli胆固醇氧化酶的分离纯化及其酶学性质研究  

Purification and Partial Characterization of Cholesterol Oxidase from Recombinant E.coli

作　　者：钟学敏[1] 张玲[1] 孙艳[1] 杨海麟[1] 王武[1] 

机构地区：[1]江南大学工业生物技术教育部重点实验室,无锡214122

出　　处：《生物技术通报》2009年第5期64-68,共5页Biotechnology Bulletin

基　　金：国家"863"计划课题资助项目(2006AA10Z305);工业生物技术教育部重点实验室基金资助项目(KLI-KF200505)

摘　　要：对重组E.coli产生的胆固醇氧化酶采用70%硫酸铵盐析、CM Sepharose FF离子层析、Phenyl Sepharose 6 Fast疏水层析、Sephadex G-75凝胶过滤,得到的胆固醇氧化酶在SDS-PAGE上呈单一蛋白质条带,酶的纯化倍数为93,收率为21%。部分酶学性质表明:酶的最适反应温度为37℃,最适反应pH7.5,热稳定范围在40℃以下,酶的pH稳定范围为6～9,分子量分别为50 kD和52 kD。酶动力学参数Km值及Vmax分别为8.2×10-5mol/L和0.21 mmol/(L.min)。In this paper, cholesterol oxidase of recombinant E. coli was purified using 70% saturation of ammonium sulfate, CM Sepharose FF chromatography, Phenyl Sepharose 6 Fast and Sephadex G-75. The purified enzyme was showed as a single band on SDS polyacrylamide gel eleetrophoresis. Part of properties of the enzyme were studied. The optimal temperature and optimal pH were 37℃ and 7.5, the temperature stability range was lower than 40℃ and the pH stability range was 6 - 9. The molecular weight was deter-mined as 50 kD and 52 kD. The Vmax value was 8.2 × 10^-5 mol/L and the Km value was 0. 21 mmol/（L, min）.

关 键 词：胆固醇氧化酶 重组E.coli 分离纯化 酶学性质 

分 类 号：Q78[生物学—分子生物学]