原生质体紫外诱变技术选育1,3-丙二醇高产菌株

Screening of 1,3-propanediol high yield strain by UV mutagenesis of protoplast

以肺炎克雷伯氏杆菌(Klebsiella pneumoniae)为研究对象,应用原生质体紫外诱变技术提高其对甘油及1,3-丙二醇的耐受性,获得1,3-丙二醇高产菌。在原生质体制备过程中,运用滤膜去除酶解后细胞悬液中的正常菌体,简化菌体酶解过程,提高再生率及形成率。经过原生质体诱变后,以耐受高浓度甘油和1,3-丙二醇及高产酸能力为筛选方向,最终筛选到了3株高产菌株(Kp-1、Kp-4和Kp-5)。在补料发酵实验中,上述诱变菌产1,3-丙二醇能力分别为70.24、65.21和75.51 g/L,比野生菌株WT(55.78 g/L)分别提高了25.92%、16.91%和35.37%。

High glycerol and 1,3-propanediol tolerance strain of Klebsiella pneumoniae was screened by ultraviolet mutagenesis of protoplast.Filtering by millipore simplified the enzymolysis process and enhance the regeneration rate and formation rate during the process of protoplast preparation.After protoplast mutagenesis,aimed at the tolerance of high concentrations of glycerol and 1,3-propanediol and high productivity of acid,three high yield mutants,Kp-1,Kp-4 and Kp-5,were obtained.In fed-batch fermentation,the volumetric productivities of above strains were 70.24 g/L,65.21 g/L,and 75.51 g/L,respectively,increased by 25.92%,16.91% and 35.37% compared with the wild type strain.