title: Increase of multidrug efflux pump expression in fluoroquinolone-resistant Salmonella mutants induced by ciprofloxacin selective pressure.
abstract: Multidrug-resistant foodborne pathogens are a leading public health concern, as antimicrobial resistance can lead to therapeutic failure. In this study, a ciprofloxacin-susceptible Salmonella Istanbul (Sal10-FC-KU12) was isolated from chicken meat obtained from a market in Korea to induce ciprofloxacin-resistant mutants (SalML, SalMM, and SalMH). Minimum inhibitory concentrations (MICs) of 12 antibiotics were measured in the presence or absence of an efflux pump inhibitor. Expression levels of efflux pump-related genes (acrB, acrF, marA, ramA, rob, and soxS) were determined using quantitative reverse transcription polymerase chain reaction (qRT-PCR). Elevated MICs for the derived mutants were shown to result from the action of the efflux pump, with increased expression of marA, ramA, and acrB compared with the wild-type strain. The results of this study suggest that continued use of ciprofloxacin might induce the emergence of Salmonella mutants resistant not only to fluoroquinolones, but also to several other classes of antimicrobials.
authors.affiliation: Laboratory of Food Safety and Evaluation, Department of Food Bioscience and Technology, Korea University, Anam-dong 5-ga, Seongbuk-gu, Seoul 136-713, Republic of Korea.
authors.forename: Hyun-Wol
authors.initials: HW
authors.lastname: Kang
authors.affiliation: Laboratory of Food Safety and Evaluation, Department of Food Bioscience and Technology, Korea University, Anam-dong 5-ga, Seongbuk-gu, Seoul 136-713, Republic of Korea. Electronic address: visionkorea@korea.ac.kr.
authors.forename: Gun-Jo
authors.initials: GJ
authors.lastname: Woo
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D002352:Carrier Proteins / Q000037:antagonists & inhibitors / Q000187:drug effects / Q000235:genetics; D002645:Chickens; D002939:Ciprofloxacin / Q000494:pharmacology*; D024901:Drug Resistance, Multiple, Bacterial / Q000187:drug effects* / Q000235:genetics; D029968:Escherichia coli Proteins / Q000037:antagonists & inhibitors / Q000187:drug effects / Q000235:genetics; D024841:Fluoroquinolones / Q000494:pharmacology*; D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects* / Q000235:genetics; D026901:Membrane Transport Proteins / Q000235:genetics* / Q000378:metabolism; D008826:Microbial Sensitivity Tests / Q000379:methods / Q000662:veterinary; D009154:Mutation / Q000235:genetics; D011202:Poultry Products / Q000382:microbiology; D056910:Republic of Korea; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods / Q000662:veterinary; D019779:Salmonella enterica / Q000235:genetics* / Q000378:metabolism
chemical_list: C000596829:AcrAB-TolC protein, E coli; D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D002352:Carrier Proteins; D029968:Escherichia coli Proteins; D024841:Fluoroquinolones; D026901:Membrane Transport Proteins; D002939:Ciprofloxacin
keywords: Antimicrobial resistance; Efflux pump; Fluoroquinolone; Salmonella enterica