Fig. 7
β-lactam susceptibility profiles and fitness of Ec ST410 strains. a β-lactam susceptibility determined by disk diffusion. Diameters are indicated in millimeters. Resistant, intermediate, and sensitive according to CLSI guidelines [16] are indicated by colors as defined in the figure keys; 32139 carries blaCTX-M15, 93G1 and 92B7 carry blaCTX-M15 and blaOXA-181, 94G8 carries blaCTX-M15 and blaOXA-181 and a mutated ftsI gene (YRIK), 83B9 and Ec-Mad belong to the OXA-181 subclade. Their position in the ST410 phylogenetic tree is indicated by stars in Fig. 1. b Minimal inhibitory concentrations (MIC) determined by Etest for selected β-lactams. c Growth curves in rich (LB and Müller Hinton, MH) and minimal (M9) medium. Curves represent the average value of 10 experiments. Box plot representations of the area under the curve of replicates determined by using growthcurver [17] are given in Additional file 4: Figure S9. Abbreviations: AMX, amoxicillin; TIC, ticarcillin; PIP, piperacillin; FEP, cefepime; CEF, cephalothin; AMC, amoxicillin-clavulanic acid; CTZ, ceftazidime; TZP, piperacillin-tazobactam; FOX, cefoxitine; CXM, cefuroxime; TCC, ticarcilline-clavulanic acid; ATM, aztreonam; MEC, mecillinam; MOX, moxalactam; CTX, cefotaxime; DOR, doripenem; ETP, ertapenem; IMI, imipenem; MER, meropenem. Antibiotic resistance gene repertoires of the 6 strains are given in Additional file 3: Table S10