Plasmid Mediated AmpC ?-Lactamase Conferring Resistance in Pseudomonas aeruginosa:A Molecular Biological Study / 中华医院感染学杂志

ABSTRACT

OBJECTIVE To study the resistance of plasmid mediated AmpC ?-lactamase in Pseudomonas aeruginosa,to detect and identify the AmpC genotype,and to provide the laboratory evidence for antibiotic reasonable application in clinics.METHODS Totally 108 strains of clinically isolated P.aeruginosa were determined antibiotic-resistant phenotype by K-B disc test,and cefoxitin three dimensional test was applied to screen AmpC positive strains.Plasmids were extracted from AmpC positive strains by SDS-alkali splitting technique.The depurated plasmid was used to amplify AmpC ?-lactamase genes by PCR.Positive PCR product was sequenced by Shanghai Sangon Biological Engineering Technology Company.Gene homology of PCR product with other index sample gene sequences was compared.RESULTS There were 28 strains producing AmpC enzyme among 108 P.aeruginosa strains.AmpC Producing P.areuginosa strains displayed multidrug-resistance to antibiotics and a new P.areuginosa strain producing plasmid mediated CMY-7 type AmpC enzyme was discoverd firstly.CONCLUSIONS Presented plasmid mediated AmpC enzyme and AmpC type ?-lactamases in P.aeruginosa are its important resistant mechanism to antibiotics.A strain producing type CMY-7 plasmid mediated AmpC enzyme is found firstly in China.