阿维菌素产生菌的诱变育种

目的提高产生菌B1a组分的产量。方法采用诱变剂亚硝基胍处理菌种 ,以含 1g·L-1甲硫氨酸的分离培养基作为定向筛选的分离平板 ,挑选生长快的菌落进行初筛、复筛。结果筛选得到高产菌株中B组分含量显著提高 ,其中得到的突变株M— 2 0经摇瓶初、复筛和传代实验表明是稳定的B组分高产变异株 ,其B组分含量达 82 1% ,较出发菌株提高 14 6 % ,其中B1组分达5 2 4 % ,较出发菌株提高 19 3%。结论采用NTG诱变结合使用含 1g·L-1甲硫氨酸的平板进行筛选可以获得阿维菌素B组分显著提高的菌株

Mutagenesis and strain-improving of avermectin-producing strain Streptomyces avermitilis

Objective To increase avermectin B 1a yield of Streptomyces avermitilis.Method NTG was used as mutagen in treating avermectin-producing strain and medium containing 0.1% methionine was used as separation plate medium to select strains growing fast on such plate.Results Strains of high-yield avermectin B were obtained,among them strain M—20 was confirmed being a stable high-yield avermectin B producer,which produced 82.1% avermectin B,14.6% higher than original strain,and B 1a content reached 52.4%,19.3% higher than original strain.Conclusion It is a effective way to obtain high-yield avermectin B 1a producer by using NTG as mutagen and using separation plate medium containing 0.1% methionine to select strains.