L-谷氨酸温度敏感突变株的选育

Breeding of L-glutamic acid temperature-sensitive mutant

采用黄色短杆菌TJ1为出发菌株,根据代谢控制发酵原理,利用紫外线、硫酸二乙酯进行诱变,定向选育出具有寡霉素抗性、谷氨酸氧肟酸盐抗性的温度敏感突变株TMGO106。然后,以温度敏感突变株TMGO106和产酸率高(10.5%以上)的天津短杆菌TG961为亲株,通过原生质体融合技术,成功地选育出了产酸率高的融合子CN1021(13.6g/dl,糖酸转化率达60%),在6m3发酵罐上中试其L-谷氨酸产量达14.6%,糖酸转化率达62.8%,并且该菌株系温度敏感型菌株,可用于谷氨酸强制发酵。

According to the theory of metabolic control fermentation,Brevibacterium flavum TJ1,as a starting strain,was stepwise treated with diethyl sulfate and ultraviolet.One temperature-sensitive mutant TMGO106was obtained,which carried about the makers of oligomycin resistance and L-glutamic acid hydroxyamate resistance.With tempera-ture-sensitive mutant TMGO106and L-glutamic high-producing strain TG961as parent strains,though protoplast fu-sion,high-producing fusion hybrid CN1021was screened successfully(13.6g/dl,the inversion rate of glucose and glu-tamic acid was60%).The product of L-glutamic acid was14.6%and inversion rate of glucose and glutamic acid was62.8%when it piloted in the6m3fermentor.This strain was temperature-sensitive and can be used as L-glu-tamic acid fermentation.