大肠杆菌可诱导启动子表达系统的构建

Construction of inducible promoter system in E.coli

大肠杆菌作为现代基因工程最为常用的原核表达系统,其核心为基因启动元件的高效性和可控性．为了获得不依赖IPTG和温度诱导的新型启动子,克隆得到大肠杆菌中通过低pH诱导的启动子Padi,并采用点突变获得几个活性各异的启动子单元,启动子的转录效率最多提高18．8倍．结果表明：该受低pH条件诱导的启动子经点位突变后,提高转录活性的同时诱导的严谨性有一定下降；在调控蛋白和启动子的协同表达后,诱导的严谨性得到提高．

A high efficient and inducible promoter system plays a key role in Escherichia coli. Padi, a new inducible promoter in the low pH environment is cloned in E. coli. The - Galactosidase assays shows the wildtype adi promoter has a lower induction than the altered promoter sequences do when the pH 8 and pH 5.5. The co - expression of adiY, increased induction ratio.