Expression, purification, and characterization of a thermophilic neutral protease from Bacillus stearothermophilus in Bacillus subtilis

作     者：ZHANG Min1,2, ZHAO Cong2, DU LianXiang2, LU FuPing2 & GAO Chen3 1 College of Engineering, Shenyang Agricultural University, Shenyang 110161, China 2 College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, China 3 College of Life Science, Nankai University, Tianjin 300071, China 

作者机构：1. College of Engineering Shenyang Agricultural University Shenyang 110161 China 2. College of Biotechnology Tianjin University of Science and Technology Tianjin 300457 China 3. College of Life Science Nankai University Tianjin 300071 China 

出 版 物：《Science China(Life Sciences)》 (中国科学（生命科学英文版）)

年 卷 期：2008年第51卷第1期

页      面：52-59页

学科分类：0710[理学-生物学] 07[理学] 08[工学] 09[农学] 071007[理学-遗传学] 0901[农学-作物学] 0836[工学-生物工程] 090102[农学-作物遗传育种] 

基　　金：Supported by the "863" High-Tech Research Project of China (Grant No. 2007AA 02Z212) 

主　　题：Bacillus subtilis thermophilic neutral protease expression purification characterization 

摘      要：The gene coding for a thermophilic neutral protease from Bacillus stearothermophilus was expressed in Bacillus subtilis DB104, under the control of the sacB gene promoter. This was followed by either the native signal peptide sequence of this protease or the signal peptide sequence of the sacB gene. The protease was purified 3.8-fold, with a specific activity of 16530 U mg-1. As analyzed by SDS-PAGE, the molecular mass of the expressed protease was about 35 kDa, and the optimal temperature and pH of the protease were 65℃ and 7.5, respectively. Moreover, it still had about 80% activity after 1 h reaction at 65 ℃ .