The mRNA expression ofompF,invA and invEwas associated with the ciprofloxacin-resistance inSalmonella

Salmonelladeveloped drug-resistance under durative antibiotic pressures pressure. The widespread prevalence ofSalmonellahas been associated with not only drug-resistance but also pathogenicity. Outer membrane porin proteins (OMPs) are critical for the drug resistance of bacteria. Virulence genes inSalmonellapathogenicity islands (SPIs) play key roles in the virulence of bacteria. In this study, we analyzed the expression levels of three critical genes in ciprofloxacin-resistant strains and ciprofloxacin-susceptible strains ofSalmonella, including outer membrane porin protein F (ompF), virulence genesinvAandinvE. In the clinical ciprofloxacin-resistant strains ofSalmonella, the expression level ofompFwas decreased. Meanwhile, the expression levels ofinvAandinvEwere decreased except for only one strain, indicating generally decreased virulence. These results were also verified with ciprofloxacin-induced resistant strains. Thus, it was informative for understanding the drug-resistance inSalmonella. Monitoring drug-resistance and virulence relevant genes would be significant in the prevention and control ofsalmonellosis.