枯草芽孢杆菌cdd基因敲除及对胞苷发酵的影响  

Knockout of the cdd Gene in Bacillus subtilis and its Influence on Cytidine Fermentation

作　　者：苏静[1] 黄静[1] 谢希贤[1] 徐庆阳[1] 陈宁[1] 

机构地区：[1]天津科技大学生物工程学院,工业微生物教育部重点实验室,天津300457

出　　处：《生物技术通讯》2010年第1期39-42,共4页Letters in Biotechnology

摘　　要：目的:通过敲除出发菌株上的胞苷脱氨酶基因,阻断嘧啶代谢通量由胞苷流向尿苷和尿嘧啶,选育胞苷产生菌。方法:采用同源重组的方法敲除枯草芽孢杆菌TS8的胞苷脱氨酶基因cdd,并通过遗传稳定性实验验证其缺失标记和胞苷产量,通过摇瓶发酵实验对比出发菌株和缺失株的产苷水平。结果:cdd基因缺失菌株TSb发酵72h,发酵液中胞苷产量达到1.72g/L,与原始菌株相比提高了44.19%,且遗传性状稳定。结论:cdd基因的缺失可有效阻断嘧啶代谢通量由胞苷流向尿苷和尿嘧啶,提高胞苷产量。Objective：To knockout cytidine deaminase gene of original strain for blocking pyrimidine metabolic flux to flow from cytidine to uridine and uracil,and to select cytidine producing bacteria.Methods：The cytidine deaminase gene cdd of Bacillus subtilis TS8 was knockouted by using homologous recombination,its resistance and production were verified through stability experiment,and the level of cytidine production between mutant and original strain was compared.Results：The mutant B.subtilis TSb accumulated cytidine 1.72 g/L after 72 h of fermentation,increasing by 44.19%compared with original strain.It also had stable heritage.Conclusion：cdd mutant B.subtilis TSb can enhance cytidine production,blocking pyrimidine metabolic flux to flow from cytidine to uridine and uracil significantly.

关 键 词：枯草芽孢杆菌 胞苷脱氨酶 同源重组 胞苷 

分 类 号：Q78[生物学—分子生物学]