劳伦链霉菌的诱变育种和发酵研究

Mutation and fermentation studies on S.laurentii

劳伦链霉菌 (S.laurentii) ATCC312 5 5是含硫多肽类抗生素硫链丝菌肽 (Tsn)的产生菌。为提高Tsn产量 ,本研究采用 UV和 NTG对劳伦链霉菌野生型进行诱变 ,筛选抗 Cu2 + 、抗氯霉素或磷霉素超敏的菌株 ,经平皿初筛 ,摇瓶复筛 ,获得两株生产能力高于母株的菌株 ,即 UFOM30 2、UCL30 10。其 Tsn产量较野生菌株提高 5 8%和 38%。又经种龄、接种量、通风量、补料等发酵条件的探索 ,突变株 UFOM30 2最终 Tsn的产量可达 190 0 μg/ ml左右 ,比野生型活力提高一倍 。

The strain improvement studies of Streptomyces laurentii were carried out by using UV radiation and NTG as mutagens. The mutants which were resistant to Cu 2+ , chloramphenicol or super sensitive to fosmomycin were isolated. Two thiostrepton high producing strains of S.laurentii , UFOM302 and UCL 3010 were selected. In the plate and shaking flasks experiments,the yields of the strains were increased by 58%and 38% respectively than the parent strain. By optimizing the fermentation conditions, the UFOM302 strain produced around 1900μg/ml thiostrepton in the shaking flasks, and could be used as a working strain for the industrial scale production of thiostrepton.