ABSTRACT
OBJECTIVE:To screen and analyze the ?-lactamases-resistant genes in imipenem-resistant pseudomonas aeruginosa (IMPRPa). METHODS: ?-lactamases-resistant genes including IMP,VIM and OprD2 in 60 clinically isolated IMPRPa strains were detected by polymerase chain reaction (PCR),and sequence analysis was performed on the PCR amplified products of some of IMP and VIM genes. RESULTS: Of the 60 IMPRPa strains,?-lactamases-resistant positive genes were as follows: IMP gene was positive in 7 strains,VIM gene was positive in 18 strains,and both IMP and VIM genes were positive in 3 strains. Sequencing of the PCR products of IMP and VIM genes were IMP-1 and VIM-2 types,and OprD2 gene deletion was noted in 29 strains. CONCLUSION: OprD2 protein channel deletion and metal-producing ?-lactamases are the chief mechanisms for the resistance of IMPRPa to imipenem.