FIG 1 .

Relative expression levels of mutants overexpressing efflux pumps. The relative expression level of the studied efflux pumps in the overexpressing mutants in comparison with the wild-type strain was measured by real-time RT-PCR. JFL30 indicates relative expression of MexAB-OprM, JFL28 indicates relative expression of MexCD-OprJ, and JFL10 indicates relative expression of MexXY. The figure shows the means and standard deviations from three different experiments. In all cases, the differences between the wild type and the overexpressing strains were statistically significant (P < 0.05).