【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.更多还原

【Abstract】 This paper reports on the two results of Ultra-Violet mutations that occurred through radiation treatments for 5 minutes.Nase activity of the selected mutant strain M-1 is higher than 540, and M-1-5-5 has drug fast of the order 400r-Km.The lowest antibiotic concentration of Km. inhibiting strains 549 and M-l varies with inoculating bacterial concentrations.lt is 1.5-6.25r/ml at 10~4 of inoculating bacterial concentration.The mutants M-l and M-l-5-5 retain basically the characteristics of original strain 549, but they grow quicker than 549 in liquid cultures.The experiments show that the drug fast gene of strain M-l-5-5 is not in the plasmid and that the drug fast is stable.更多还原