The ArcAB system is dispensable for H
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.