百脉根根瘤菌MAFF303099 Tn5转座子插入突变体库的构建及筛选
Constructing and screening a Tn5 transposon inserted mutant library of Mesorhizobium loti MAFF303099

以百脉根根瘤菌MAFF303099为材料，利用转座子Tn5-sacB转座技术得到了约10000个MAFF303099的转座接合子，构建随机插入突变体库进行保藏；同时建立了一套能从突变体库中快速筛选突变菌株的方法，且鉴定到共同结瘤基因nodB的突变体。结果表明：组成突变体库的接合子基因组中均有Tn5-sacB插入，三亲本转化效率为3.75×10-5；与野生型相比，MAFF303099 nodB的突变体在表型上不能使其宿主百脉根形成根瘤。
Mesorhizobium loti MAFF303099 was used to construct a random mutant library with transposon Tn5-sacB mutagenesis technique.A total of about 10000 independent mutants were obtained.A method for rapidly identifying mutants from the library was established.The mutant of the symbiotic nodule gene nodB was identified through screening the mutant library.The results showed that the transposon Tn5-sacB was inserted into the genome DNA of all the mutants in the mutant library,with the tri-parental mating transformation efficiency of 3.75×10-5.The MAFF303099 mutant of nodB did not form nodules on Lotus japonicus roots comparing with the wildtype.