多杀菌素高产菌株的选育

根据多杀菌素的生物合成途径对多杀菌素产生菌株刺糖多孢菌(Saccharopolyspora spinosa)进行选育,并获得了高产菌种。首先对出发菌株S-203进行了自然选育,获得效价为643μg.mL-1的菌株S-306;在紫外线诱变的基础上,筛选丙酸钠耐性变株,得到菌株S-466,摇瓶发酵单位为871 mg·L-1,比自然选育获得的出发菌株提高了35%。其传代实验表明菌株S-466的高产遗传特性稳定,为应用于发酵罐进行工业化生产奠定了基础。

Screening of spinosads-producing strain with high yield

According to the biosynthetic pathway of spinosads produced by Saccharopolyspora spinosa,a rational selection was performed to obtain high spinosads-producing strain.Saccharopolyspora spinosa S-306 was selected with the yield of 643 μg·mL-1 after natural selection of S-203.A strain S-466 was got after combination of UV mutation and propionate-resistance screening.Its production of spinosads reached 871 mg·L-1,which was 35% higher than that of the ancestral strain S-466.The subculture experiments indicated that the hereditary char-acteristic of high productivity of S-466 was stable,which was favorable for large scale spinosads production.