摘要： 为使地衣芽孢杆菌信号肽序列实现异源基因在大肠杆菌中的分泌表达,将地衣芽孢杆菌中编码耐高温α-淀粉酶的基因克隆在大肠杆菌表达载体pET-22b的T7启动子下游,转化大肠杆菌BL21(DE3)。重组菌株经乳糖诱导后,在上清液中能够检测到淀粉酶活性。表明该芽孢杆菌淀粉酶基因5′端信号肽序列能够将大肠杆菌中的重组α-淀粉酶引导到胞外,完成分泌表达。同时,用该信号肽序列还实现了甜蛋白monellin基因在大肠杆菌中的分泌表达。

关键词: &alpha, -淀粉酶, 地衣芽孢杆菌, 分泌表达, 信号肽

Abstract: The gene encoding a hyperthermostable α- amylase from a Bacillus licheniformis strain was cloned in p ET-22b transcription vector containing T7 promoter,and expressed in Escherichia coli BL21 (DE3) cells. The recombinant strain can secret the active recombinant enzyme into the medium. These indicated the signal peptide of this Bacillus sp.could be recognized by E. Coli secretory system. At the same time,the signal peptide secreted sweet protein monellin fromperiplasm to the medium too.This study gives a theory support for other foreign proteins expressed in E. Coli through theuse of this signal peptide.

Key words: &alpha, - amylase, Bacillus licheniformis, Secretory expression, Signal peptide

中图分类号: 

• Q81