Figure 3
From: Reactive oxygen species do not contribute to ObgE*-mediated programmed cell death
Scavengers lower ROS concentrations but do not influence ObgE*-mediated toxicity.
Exponential-phase cultures of E. coli pBAD33, E. coli pBAD33-obgE or E. coli pBAD33-obgE* were induced with 0.2% arabinose for 2 hours and ROS-scavengers DMSO, sodium pyruvate and MnTBAP were simultaneously added to the culture. (a) The combination of ROS scavengers lowers the activity of the redox-sensitive promoter PsoxS. As a positive control 20 mM paraquat (PQ) was used. Thick lines represent samples to which scavengers were added. (b) The combination of ROS scavengers lowers the activity of the H2O2-responsive promoter Pdps. As a positive control 100 μM H2O2 was used. Thick lines represent samples to which scavengers were added. (c) The combination of ROS scavengers, or of each scavenger separately, has no effect on survival upon expression of ObgE*. Error bars represent the standard error of the mean, n = 4. Student’s t test: not significant (α = 0.05) in comparison with ‘No scavengers’.
