降烟碱解淀粉芽孢杆菌和边缘假单胞菌原生质体融合选育高效降烟碱菌株

    Protoplast fusion between nicotine-degrading Bacillus amyloliquefaciens and Pseudomonas marginalis to breed efficient nornicotine strain

    • 摘要: 获取1 株高效降解烟碱的融合子,以解淀粉芽孢杆菌T11 和边缘假单胞菌作为亲本菌株,使用溶菌酶破除亲株细胞壁后以40%PEG-6000 诱导解淀粉芽孢杆菌T11 原生质体和已热力灭活的边缘假单胞菌原生质体进行融合,并检测了融合子的降烟碱能力。对融合子利用青霉素抗性初筛获得了176 株再生融合子,利用烟碱降解率为指标进行降烟碱复筛实验后获得5 株烟碱降解能力较高的融合子。根据融合子遗传稳定性分析及与亲本菌株烟碱降解效率的对比,获得了1 株烟碱降解率比亲本菌株更强的融合子A2。获得的高效降解融合子A2 在第5 天后其烟碱降解率基本稳定在93%。

       

      Abstract: In order to acquire fusant with high nicotine-degrading ability,Bacillus amyloliquefaciens T11 and Pseudomonas marginalis were used for parent strains. After using lysozyme to break the cell walls of parent strains, the Bacillus amyloliquefaciens T11 protoplast and heat-inactivated Pseudomonas marginalis protoplast were induced by 40% PEG-6000 for protoplast fusion experiment,then the nicotine-degrading ability of fusant was measured. Through preliminary screening,176 fusion strains were obtained. After rescreening by nicotine selective culture medium,5 fusion strains with higher nicotine-degrading ability were acquired. Genetic stability analysis of the 5 fusion strains and comparision with parent strains’ nicotine-degrading rate were further measured. A better fusant A2 with higher nicotinededrading ability than parent strains was obtained finally,93% nicotine in culture medium was degraded in five days.