Genetic Characterization of Carbapenemase-Producing Enterobacter cloacae Complex and Pseudomonas aeruginosa of Food of Animal Origin from Egypt

The increasing spread of carbapenem resistance is a serious global public health concern that negatively affects human and animal health. In this study we characterized the carbapenemase production in gram-negative bacteria isolated from different meat and meat products in Egypt. Phenotypic and genotypic susceptibility testing were investigated. TwoEnterobacter cloacaecomplex strains, isolated from kofta and beef burger, and onePseudomonas aeruginosaisolated from minced meat, were found to harbor VIM-1 and VIM-2, respectively. These isolates showed multidrug resistance phenotype. The phenotypic carbapenemase production was confirmed with Carba NP test in addition to modified Hodge test, modified carbapenem inactivation method, and ethylenediaminetetraacetic acid inhibition test. Thebla(VIM-1)gene in both non-clonally relatedE. cloacaecomplex strains was part of a class 1 integron that also carried other resistance gene cassettes such asaacA7,dfrA1,Delta aadA, andsmr. This integron was uncommonly disrupted by the insertion sequence ISPa21, located on a self-conjugative plasmid of either the A/C or HI2 incompatibility group with a size of >93 kb. Thebla(VIM-2)gene was identified within a class 1 integron, followed downstream by resistance genesaadBandbla(OXA-10). The transfer ofbla(VIM-2)gene fromP. aeruginosafailed, suggesting that this gene was located on the chromosome. Further studies are needed to screen the dissemination of carbapenemase-producing bacteria in both the environment and food chain.