Additional file 1 of Chromogenic Escherichia coli reporter strain for screening DNA damaging agents

Additional file 1: Figure S1. Additional controls used in this study. Panel A shows the expression of AmilCP under the control of the uspA (Universal Stress Protein) promoter sequence. As an activating agent, H2O2 was used and mitomycin C as a negative control (MC). Panel B shows the effect of varying concentrations of SDS on the activation of the recA reporter strain. Panel C shows the activation of varying concentrations of ethanol. Panel D shows the viability and activation of the reporter strain during a 30 min. heat shock. The clear area on each experiment indicates cell death. The purple halos indicate reporter strain activation. Panel E, representative examples of 35 mm petri dish assays using MC at different concentrations and the plot of halo diameter against MC concentration, an average of three independent experiments, to show that below 1 µg of MC the signal is barely detectable. Figure S2. Evaluation of lower concentrations of the chromium contaminated lixiviates from a chromite processing facility. Panel A shows the activation of the reporter strain at lower concentrations of the Cr(VI) containing lixiviates. In Panel B, control lixiviates are shown from the mountainside of the contaminated soil known to be clear of Cr(VI). The clear area on each experiment indicates cell death. The purple halos indicate reporter strain activation.