Figure 2.

The ArcAB system is dispensable for H₂O₂ scavenge. The ΔarcA (square), ΔarcB (triangle) mutant and the wild type E. coli K12 (diamond) was cultured in LB broth supplemented with 2 mM of H₂O₂ at 37°C with shaking. Bacterial concentration and the H₂O₂ concentration were measured at various time points. The H₂O₂ scavenge was measured as the decrease of H₂O₂ concentration per 10⁷ c.f.u. bacteria. A control sample without bacteria (cross) was included to monitor any possible spontaneous degradation of H₂O₂. The experiment was repeated at least three times, and data from one representative assay performed in duplicates were shown. Error bars indicate standard deviation and sometimes fall within the data label.