摘要
目的:筛选得到胞苷发酵单位较高的菌株,并对发酵过程作初步研究。方法:以胞苷脱氨酶缺失枯草芽孢杆菌DOS7为出发菌株,对其进行紫外诱变、5-氟胞苷(5FCR+)和2-杂氮尿嘧啶抗性(2AU+)抗性筛选。结果:通过紫外诱变和抗性筛选得到突变株DOS7-2-1000-15,抗5-氟胞苷和2-杂氮尿嘧啶的临界浓度分别为800mg/L和1 000mg/L。同时检测了抗5-氟胞苷突变株中CTP合成酶的活性,比原始菌株提高了12.4%,突变株DOS7-2-1000-15发酵过程结果为:36℃发酵72h能积累胞苷最高为3.5g/L。结论:筛选得到的突变株DOS7-2-1000-15的遗传稳定性较好,可稳定发酵。
In order to obtain a mutant which can increase the yield of cytidinc and study the process of cytidine fermentation. Meth- ods： Screened from DOS7 （deficient in cytidine deaminase） by ultraviolet, 5FCR and 2AU resistance mutagenesis. Results： Obtained a mutant Bacillus subtilis DOS - 2 - 1000 - 15, had the ability of 5FCR and 2AU resistance. The resistance critical concentration of 5FCR and 2AU was 800mg/L and 1000mg/L respectively. The activity of the CTP synthetase from the 5FCR resistance mutant was increased 12.4% more than the starting mutant. The strain could secreted 3 .5g/L cytidinc at 36℃ after 72h fermentation. Conclusion： Genetic stability and fermentation stablity of the mutant Bacillus subtilis DOS- 2- 1000- 15 were good.
出处
《生物技术》
CAS
CSCD
2007年第5期57-59,共3页
Biotechnology
关键词
胞苷
枯草芽孢杆菌
菌种选育
发酵
cytidine
Bacillus subtilis
strain screen
fermentation
