乙型肝炎病毒preS1 多肽在大肠杆菌中的表达与纯化研究

Studies on expression and purification of hepatitis B virus preS1 polypeptide in E.coli

目的 获得大量完整的重组乙肝病毒（ Ｈ Ｂ Ｖ）ｐｒｅ Ｓ１ 多肽纯品，以利于ｐｒｅ Ｓ１ 功能与免疫学性质的研究。方法 比较不同表达载体及不同的培养、诱导和纯化条件，最大限度地使表达产物免受大肠杆菌蛋白酶的降解。结果 分析不同长度ｐｒｅ Ｓ１ 基因在两种不同载体，两种表型宿主菌中表达产物的状况，可看出在ｐｒｅ Ｓ１ 第５６ 和６４ 位氨基酸之间存在两个 Ｅ．ｃｏｌｉ 蛋白酶切割点。用ｐ Ｑｅ９载体和 Ｍ１５（ｐ Ｒ Ｅ Ｐ４） 宿主菌， Ｉ Ｐ Ｔ Ｇ 诱导１２ 小时以 Ｎｉ Ｎ Ｔ Ａ 琼脂糖柱在变性条件下纯化，能获得１０ ｍｇ／ Ｌ 以上具有良好免疫学活性的电泳纯ｐｒｅ Ｓ１ 蛋白。结论 缩短诱导时间、用一步法在变性条件下纯化表达产物可获得无明显降解的ｐｒｅ Ｓ１ 完整蛋白。

Studies on expression and purification of hepatitis B virus preS1 polypeptide in E.coli$$$$ HAN Baoguang*,Eberhard Hildt,MA Xiankai,et al. *Institute of Basic Medical Sciences of AMMS, Beijing 100850 【Abstract】 Objective To obtain large amount of full length pure recombinant HBV preS1 protein for studies on its function and immunogenecity. Method Comparing effects of different expression vectors,cultural,induction and purification conditions on minimizing degradation by bacterial protease on the gene product. Results Two E.coli  protease cleavage sites existed between preS1 5665 amino acids.Through using pQe9 vector and M15(pREP4) host cell,reducing the induction time,and carrying out affinity purification under denaturing condition,we succeeded in obtaining 10mg/L of pure preS1 1119 . Conclusion By cutting down the induction time and doing purification under denaturing condition one can obtain full length preS1 protein free from apparent degradation product. 【 Subject words 】 Hepatitis B virus preS1 polypeptide