Ompk36 disruption and expression of down-regulated blaKPC-2 in Klebsiella pneumoniae clinical isolates carbapenem resistant

Abstract

This work investigated the resistance mechanisms that produce different susceptibility profiles in Klebsiella pneumoniae clinical isolates. The genes that encode the main porins in K. pneumoniae, ompK35 and ompK36, and several beta-lactamase genes were analyzed. The expression of these genes was evaluated by quantitative real time PCR (polymerase chain reaction) with reverse transcriptase (RT-qPCR). SDS-PAGE (sodium dodecyl sulphate–polyacrylamide gel electrophoresis) was performed to analyze the outer membrane proteins. The analysis of the ompK36 genetic environment found the presence of the IS903 insertion sequence interrupting this gene in the ertapenem resistant isolate (KPN133). The blaKPC-2 gene showed down-regulated expression in both isolates.