ABSTRACT
Objective The construction of suicide plasmid vector could be used to make mutation of pgm gene which attenuates the virulent of Brucella melitensis strain 16, the research may lay a foundation for the development of novel live attenuated vaccines. Methods Sucrose sensitive gene as forward screening sign and fusion sequences of kanamycin resistance gene were constructed based on plasmid pucl9; pucS1.6K suicide plasmid vector was established by modifying pgm gene with fusion sequences of kanamycin resistance gene (insertion mutation); pgm gene mutation of Brucella melitensis strain 16 was obtained by electro transformation and mutation was confirmed by PCR amplification. Results The results showed that the identified Brucella melitensis strain 16 pgm gene was inactivated after insertion of kanamycin resistance gene, and the mutant pgm gene DNA fragment length was approximately 3525 bp, in line with expectations, Brucella pgm gene mutant melitensis strain 16 was successfully constructed. Conclusions The construction of suicide plasmid vector and precise mutation of Brucella melitensis strain 16 is successful, the study is not only provided an effective technology platform for constructing mutants of Brucella but also lays a foundation for the development of novel live attenuated vaccines.