摘要： 本文报道了用紫外线诱变的方法处理菌株(K.pneumoniae)549,经两次诱变处理,分别筛选到一株具有抗Km400γ的菌株M-1-5-5和一株固氮活性较高的菌株M-1.Km对549和M-1的最低抑菌浓度随着涂皿浓度的变化而改变,菌液浓度10~4时,抑菌浓度为1.5—6.25单位/毫升.突变菌株M-1和M-1-5-5基本保持原出发菌株549的特征,在液体培养时M-1和M-1-5-5的生长速度比549快.试验表明M-1-5-5的抗性基因不在质粒上,连续传代试验说明其抗性具有稳定性.

关键词: 紫外线, 诱变, 联合固氮

Abstract: This paper reports on the two results of Ultra-Violet mutations that oc-curred through radiation treatments for 5 minutes.N ase activity of the selected mutant strain nl-1 is higher than 549, and 1\I-1-5-5 has drug fast of the order 400r-Km. The lowest antibiotic concentration of Km.inhibiting strains 549 and M-1 varies with inoculating bacterial concentrations.It is 1.5-6.25r/ml at 10' of inoculating bacterial concentration. The mutants M-1 and M-1-5-5 retain basically the characteristics of origi-nal strain 549,but they grow ctuiclier than 549 in liquid cultures. The experiments show that the dr ug fast gene of strain M-I-J-J is not in the plasmid and that the drug fast is stable.

Key words: Mutagen, Ultra-violet, Associatve N2-fxng battera