Two suicide vectors of pww and pvv carrying the 871bp segment ofadhe and 805bp segment of idha amplified by pcr respectively were constructed and six mutants ofadhe and four mutants of ldha - were obtained by homogenous recombination between the partial adhe or idha in the vectors and the klebsiella pneumoniae m5al chromosome Pcr扩增出产乙醇途径adhe基因的部分片段和产乳酸途径ldha基因的部分片段，构建了分别带有部分adhe基因片段和部分ldha基因片段的自杀质粒pww和pvv ，通过同源重组的手段分别得到了6个adhe ~ -突变株和4个ldlm ~ -突变株。
