带自身启动子的bgaB基因在枯草芽孢杆菌中的表达

The Expression of bgaB Gene with its Promoter in Bacillus subtilis

将来源于嗜热脂肪芽孢杆菌的启动子连同β-半乳糖苷酶bgaB基因经PCR扩增后,连接在T载体上,再取代枯草杆菌载体pZ01-bgaB的启动子,将其在枯草杆菌宿主WB600中表达.经摇瓶发酵20h,得到乳糖酶活力6.37U/mL,比活力3.814U/mg,SDS-PAGE电泳显示有明显重组蛋白质条带.证明了嗜热脂肪芽孢杆菌来源的启动子在枯草杆菌中是完全适用的.

The promoter and gene sequence from Bacillus stearothermophilus were amplified through PCR, and cloned into T-vector. Then bgaB gene and its regulatory sequence were constructed into B. subtilis vector pZ01-bgaB to replace the original promcter. After culturing for 20 h, thermostable β-galactosidase activity of 6. 37 U/mL, and specific activity of 3. 814 U/ mg were obtained. The target protein was identified at about 70 kD in SDS-PAGE. The result suggested that the bgaB promoter from B. stearothermophilus was effective in B. subtilis.