【摘要】 为了提高枯草芽孢杆菌B4的蛋白酶产量,采用全基因组改组技术进行菌株选育,先通过紫外诱变构建了B4菌的突变体库,在优化其原生质体制备和再生条件的基础上,以其中4株诱变菌株(BRS1、BRS2、BRS5、BRS6)作为亲本,采用PEG介导的方法进行两次多亲本的全基因组改组,同时,结合双亲灭活的筛选方法,共筛选出3株酶活力大幅度提高并能稳定遗传的优良菌株,为BRS1、BRS5、BRS6,酶活力最高达2175.81U/mL,达到原始菌株的3.01倍。更多还原

【Abstract】 Whole genome shuffling technique was used to enhance protease production by Bacillus subtilis B4.A candidate mutant library was constructed by UV irradiation of Bacillus subtilis B4.Based on the optimum conditions for protoplast preparation and regeneration,multi-parental whole genome shuffling was carried out with 4 mutant strains(BRS1,BRS2,BRS5 and BRS6) by PEG mediated protoplasts fusion.Then BRS1,BRS5 and BRS6 were identified by biparental inactivation method as 3 excellent strains with greatly improved protease activity and good genetic stability.The maximum activity was as high as 2175.81 U/mL,which was increased 3.01 fold compared with the initial strain B4.更多还原