Fig. 2.

Dissipation of the proton motive force leads to a significant decrease in gentamicin toxicity A E. coli EC958 cells grown aerobically in M9 minimal media supplemented with 0.1% casamino acids were exposed to ± 1 mM DNP for 30 min followed by incubation with varying concentrations of gentamicin for 90 min. This was followed by serial dilutions, spotting on LB agar and overnight incubation at 37 °C to enumerate CFU/mL. Mean % survival values are shown ± standard deviation from 2 biological repeats each with 3 technical repeats. B E. coli EC958 cells grown aerobically in M9 minimal media supplemented with 0.1% casamino acids were exposed to ± 1 mM DNP for 30 min. Cells were harvested and the electrical potential of the PMF was measured with a plate reader using the fluorescent dye DiSC₃(5) (2 µM). Control experiments were performed without DNP and without cells (i.e. buffer only). Data in the figure are at time point 2452 s and are averages of six repeats including two biological repeats for each condition. Data expressed as % relative to the negative control. (One-way ANOVA with Tukey’s post hoc tests: ****P value < 0.0001, ***P value < 0.001, **P value < 0.01)