大气压冷等离子体诱变产1，3-丙二醇菌株Klebsiella pneumoniae

Mutagensis of Strain Klebsiella pneumoniae Producing 1,3-Propanediol by Cold Plasma at Atmospheric Pressure

采用大气压冷等离子体介质阻挡放电法对产1,3-丙二醇的克雷伯氏菌进行诱变,采用诱变与筛选同时进行的单细胞平板诱变方法,同时获得了可耐受高浓度甘油且1,3-丙二醇产量较高的优良突变株.对诱变后菌的间歇发酵结果表明,诱变菌株比出发菌株1,3-丙二醇的质量转化率提高了23%,对数期比生长速率提高了18%.批式流加发酵过程中,1,3-PD浓度在发酵36h时达到70.5g/L,甘油的质量转化率为0.57g/g,分别比野生菌提高47%和58%.该诱变和筛选方法具有操作简单、效率高等特点,对具有工业应用价值的菌株筛选具有实用价值.

An efficient agar plate mutagensis and screening technique for improving mutation frequency and simplifying operation was established by using dielectric barrier discharge plasma. Klebsiellapneumoniae producing 1,3-propanediol （1,3-PD） was used as a model strain. A positive mutant strain （K. 81206） was selected, which can endure a high concentration of glycerol, and produce high concentration of 1,3-PD. The results of batch fermentation by K. 81206 showed that the yield of 1,3-PD from glycerol was increased by 23% and the maximum specific growth rate was increased by 18% at logarithmic phase, respectively, compared with control strain. The fed-batch fermentation showed that the 1,3-PD concentration increased to 70.5 g/L and yield of 1,3-PD from glycerol was 0.57 g/g, which means 47% and 58% increase compared with the wild strain, respectively. These results demonstrated that the agar plate mutagensis and screening technique would be useful in the industrial biological production of 1,3-PD as well as other chemicals produced by industrial microorganisms.