枯草芽孢杆菌中一种新型双向启动子的功能鉴定

Characterization of a novel bidirectional promoter in Bacillus subtilis

本研究旨在通过转录组分析预测的方法,由地衣芽孢杆菌中筛选获得一种新型双向启动子,鉴定其启动强度。以已知强组成型启动子pShuttle-09为对照,检测其对克劳氏芽孢杆菌碱性蛋白酶基因的表达活性。成功构建了3种重组碱性蛋白酶表达载体及对应的工程菌株。在新型启动子pLA和其反向启动子pLB调控转录下,克劳氏芽孢杆菌碱性蛋白酶表达活性达到164U/mL和111U/mL。结果表明,pLA的启动强度明显高于pShuttle-09和pLB,pLA启动子与pLB启动子均可表达碱性蛋白酶。从而为枯草芽孢杆菌表达系统中异源基因的表达提供一个新的方向,也为原核生物中共同表达两种基因提供了新的思路。

Based on the transcriptome analysis data of a Bacillus licheniformis,a novel bidirectional promoter was identified from the strain and its transcriptional strength was analyzed.The expression level of a Bacillus clausii derived alkaline protease gene driven by the bidirectional promoter was studied by using the known strong constitutive promoter pShuttle-09 as a control.Three recombinant expression vectors and the corresponding recombinant bacteria were constructed.Under the control of the new promoter pLA and its reverse promoter pLB,the alkaline protease expression level respectively reached 164 U/mL and 111 U/mL.The results indicated that the transcription strength of pLA was significantly higher than that of pShuttle-09 and pLB,and both the pLA and pLB promoters could initiate the expression of the alkaline protease.Thus,it provides a new expression element for the heterogenous genes in Bacillus sp.and a new idea for the co-expression of two genes in one prokaryotic strain.