L-苏氨酸产生菌的原生质体融合育种研究

Breeding and fermentation conditions of L-threonine producing strains

采用原生质体融合等技术,以谷氨酸棒杆菌GY360(Met-+AECr+AHVr)为亲株(A)与乳糖发酵短杆菌HS58(Ala-+AHVr)为亲株(B)进行原生质体融合,选育出一株产L-苏氨酸菌NRH66,该菌株遗传标记为Met-+Ala-+AECr+AHVr,在摇瓶上发酵可产L-苏氨酸46.2g/L,比亲株A产酸提高了17.7%,比亲株B产酸提高64%。

Strains Corynebacterium glutamicum GY360 （Met＋AEC^r＋AHV^r） and Lactobacillus brevis HS58 （Ala＋ AHV^r） were respectively used as parent strain A and B for protoplast fusion. An acid L-threonine producing strain NRH66 was obtained and its genetic markers were Met ＋ Ala ＋ AEC^r＋ AHV^r. L-threonine production was 46.2g/L for the bred strain in liquid fermentation in shake flask, which was 17.7% and 64% higher than that of parent strain A and strain B, respectively.