Figure 1
From: Reactive oxygen species do not contribute to ObgE*-mediated programmed cell death
ObgE* increases intracellular ROS concentrations.
(a) Cultures of E. coli pBAD33, E. coli pBAD33-obgE or E. coli pBAD33-obgE* were stained with the redox-sensitive probe H2DCFDA that can be oxidized to form the fluorescent H2DCF. ObgE* expression increases H2DCF fluorescence, even when the signal is corrected for cell size and thus causes oxidative stress. PC = Positive Control, E. coli pBAD33 + 100 μM H2O2. (b) ObgE* activates GFP expression from the ROS-responsive promoters PsoxS and Pdps and therefore leads to increased ROS concentrations. PC = Positive Control, E. coli pBAD33 + 20 mM PQ for PsoxS and E. coli pBAD33 + 100 μM H2O2 for Pdps. Representative results of three repeats are shown. (c) Average GFP expression from the ROS-responsive promoters PsoxS and Pdps shows that ObgE* expression leads to increased ROS concentrations. Averages of three repeats are shown. Error bars represent the standard error of the mean, n = 3. Student’s t test: #p-value < 0.05, ##p-value < 0.01 in comparison with the vector control.
