温度和氮源对耐冷蜡状芽孢杆菌产冷适蛋白酶的影响  

Effect of Termperature and Nitrogen Source on Psychrotrophic Bacillus Cereus SYP-A2-3 Production Cold-Adapted Protease

作　　者：史劲松[1] 陶文沂[1] 许正宏[1] 吴奇凡[1] 窦文芳[1] 

机构地区：[1]江南大学生物工程学院,江苏无锡214036

出　　处：《南京师大学报（自然科学版）》2005年第4期77-82,共6页Journal of Nanjing Normal University(Natural Science Edition)

基　　金：国家"863"计划资助项目(2001AA214101)

摘　　要：对影响耐冷蜡状芽孢杆菌SYP-A2-3合成冷适蛋白酶的主要因素进行了研究,主要包括培养温度对产酶水平和产酶周期的的影响、不同相对分子质量分布的酪蛋白水解物对菌体细胞诱导产酶的差异以及菌体芽孢形成过程与产酶过程的关系等.结果表明通过采取前高后低的变温培养策略可以使菌体在发酵初期快速增殖,从而提高冷适蛋白酶的产量,粗料氮源预水解可增加相对分子质量较低的氮源水平,能提高前期的菌体产量.研究认为,在产酶期间应保持低分子量氮源的低速释放,使诱导作用得到持续加强并减缓代谢阻遏作用,避免芽孢的快速形成,实现产酶期的延长.The key factors on synthesizing cold-adapted protease with psychrophlic Bacillus Cereus SYP-A2-3 were investigated. They mainly included the effect of different culture temperatures on the production course and protease level, the ability to induce protease by the different molecular weight distribution of casein peptide, and the relationship between spores formation and production protease. The optimization control strategy for fermentation was adopted so that protophase culture should be in higher temperature （20℃） in order to increase biomass and that production enzyme should be in lower temperature （15℃） in order to raise protease yield. When coarse nitrogen source was applied in the medium, it should be prehydrolysised to increase concentration of LMWN （lower molecular weight nitrogen）. During the course of production protease, the LMWN should be kept slowly releasing to medium in order to strengthen induction and decrease metabolic repression, and that it was important to prolong the course of production protease and to avoid sproutation at a short time.

关 键 词：蜡状芽孢杆菌 适冷菌 诱导和阻遏 蛋白酶 

分 类 号：Q936[生物学—微生物学]