出发菌株经紫外照射诱变后，再采用激光复合诱变方式进行的筛选，并对其传代稳定性进行研究，以期进一步获得稳产高产那西肽产生菌突变株。结果表明紫外照射100s得到的NXT-U19放瓶效价比出发菌株（546．17μg／mL）提高了44．22％，达到了787．71μg／mL。激光-紫外复合诱变后筛选出6株产量较高的菌株，其中以NXT—U19-J2效价最高，比原始菌株提高了65．74％，达到了905．22μg／mL。经传代培养分析，NXT—U19-J2诱变株的遗传稳定性较好，该结果表明，激光复合诱变是获得高产那西肽产生菌的有效途径。%The starting strain was treated by ultraviolet irradiation, then it was screened further by laser compound mutation and studied on the genetic stability to obtain the stable high-yield nosiheptide-producing strains. The result showed that the potency of strain NXT-U19 was increased by 44.22% compared to the original strain （546.17 μg/mL）, reaching 787.71 μg/mL. Six high-yield strains was screened by laser-ultraviolet compound mutation, among them the highest potency of strain NXT-U19-J2 was increased by 65.74% compared to the original strain, reaching 905.22 μg/mL. The analysis of subculture proved that the genetic stability of mutated strain NXT-U19-J2 was good. This result has showed that laser compound mutation is the efficient method to obtain the high-yield nosiheptideproducing strains.
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