目的 筛选获得高产多黏菌素E的菌株.方法 以多黏类芽孢杆菌(P.polymyxa 1-8)为出发菌株,采用亚硝基胍-60钴复合诱变,以多黏菌素E和α-氨基丁酸作为筛选因子,采用平板抑菌圈法初筛,筛选获得高产多黏菌素E的高产菌株.结果 获得一株效价较出发菌株P.polymyxa 1-8提高35.7％的遗传稳定突变株P.polymyxa B-23,其摇瓶发酵效价达到7.8万U/mL.结论 平板抑菌圈法作为初筛方法能极大的提高筛选效率,有助于获得高产菌株.%Objective Screening of polymyxin E high-yielding mutants. Methods The original strain P. polymyxa 1-8 producing polymyxin E was treated with NTG-60Co-γ. With polymyxin E as selection factor and NTG as mutagen, a high-yielding strain P. polymyxa 1-8 A-43 was obtained by firstly plate inhibition zone screening technique and then flask fermentation selection, whose polymyxin E production was increase by 21% compared with parent strain. Successively, using 60Co-γ treatment of P. polymyxa A-43, with L-y-aminobutyric acid as selection factor and by the same screening protocol as above. Results P. polymyxa B-23 was obtained with 35.7% yield increase than original strain P. polymyxa 1-8, whose flask fermentation level arrived at 78,000U/mL. Conclusion Plate inhibition zone screening technique is useful for screen high-yielding mutants.
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