Construction of blaNDM-1gene deletion mutant of Enterobacter cloacae and analysis of its biological characteristics / 中华微生物学和免疫学杂志

ABSTRACT

Objective To construct a blaNDM-1gene deletion mutant of Enterobacter cloacae and to analyze its biological characteristics. Methods The blaNDM-1gene deletion mutant was constructed by using Red homologous recombination technology and verified by PCR and RT-qPCR. Antimicrobial susceptibility profiles,growth curves and in vitro competition abilities of the original strain and the blaNDM-1gene deletion mutant were analyzed. Results PCR,DNA sequencing and RT-qPCR showed that the blaNDM-1gene dele-tion mutant was successfully constructed. Antimicrobial susceptibility test showed that the original strain was resistant to imipenem,meropenem and ertapenem, while the blaNDM-1gene deletion mutant was sensitive to all. The original strain and the blaNDM-1gene deletion mutant had similar growth curves in Luria-Bertani liq-uid medium. In vitro competition experiment revealed that the competitive index of them was 0.69. Conclu-sion Red homologous recombination technology can be used to knockout the blaNDM-1gene of Enterobacter cloacae,which is associated with antimicrobial resistance and competitiveness.