Background and Aim: Pseudomonas aeruginosa is a highly drug - resistant and opportunistic pathogen. The MexAB - OprM efflux pump contributes to the intristic resistance to various antimicrobial agents in Pseudomonas aeruginosa isolated from patients. The aim of this study was to evaluate the expression of MexAB - OprM efflux pump such as MexA, MexR and gyrA as housekeeping genes using Quantitative Real - Time PCR method in ATCC 27853 strain and resistant clinical isolates.
Methods: In this cross - sectional study, resistant clinical isolates were performed using disk diffusion and broth microdilution methods according to CLSI protocols. The expression of MexA, MexR and gyrA were analyzed in resistant clinical isolates and ATCC 27853 stra in in the absence drug and presence of the drugs gentamicin, piperacillin and gentamicin/ piperacillin combination.
Results: There was relatively fixed expression level of gyrA gene as the housekeeping gene in ATCC 27853 strain and resistant clinical isola tes. In the compared combined with single dose of the drugs with an intended MIC concentration, was reduced in MexA gene expression, but the MexR gene expression was increased in 27853 ATCC strain and resistant clinical isolates Pseudomonas Aeruginosa.
Conclusion: The analysis of molecular mechanism of the possible effects of other effective genes in creating resistance phenomenon could be evaluated using other techniques of analyzing gene expression.