ramR mutations affecting fluoroquinolone susceptibility in epidemic multidrug-resistant Salmonella enterica serovar Kentucky ST198

Sylvie Baucheron (1, 2) , Simon Le Hello (3) , Benoît Doublet (1, 2) , Etienne Giraud (1, 2) , François-Xavier Weill (3) , Axel Cloeckaert (1, 2)

1 UT - Université de Tours
2 UMR ISP - Infectiologie et Santé Publique
3 BPE - Bactéries pathogènes entériques

A screening for non-target mutations affecting fluoroquinolone susceptibility was conducted in epidemic multidrug-resistant Salmonella enterica serovar Kentucky ST198. Among a panel of representative isolates (n = 27), covering the epidemic, only three showed distinct mutations in ramR resulting in enhanced expression of genes encoding the AcrAB-TolC efflux system and low increase in ciprofloxacin MIC. No mutations were detected in other regulatory regions of this efflux system. Ciprofloxacin resistance in serovar Kentucky ST198 is thus currently mainly due to multiple target gene mutations.

Keywords: Salmonella; ram; efflux pump; ciprofloxacin resistance; regulation

Domains: Santé publique et épidémiologie

Sylvie Baucheron, Simon Le Hello, Benoît Doublet, Etienne Giraud, François-Xavier Weill, et al.. ramR mutations affecting fluoroquinolone susceptibility in epidemic multidrug-resistant Salmonella enterica serovar Kentucky ST198. Frontiers in Microbiology, 2013, 4, pp.1-6. ⟨10.3389/fmicb.2013.00213⟩. ⟨pasteur-01109819⟩