Stress survival of (p)ppGpp-dependent regulator mutants. Survival of the wild type, ecfG2 mutant, rpoE4 mutant, ecfG2-rpoE4 mutant and CH00371 mutant was determined by plating on TY medium after stress treatment and is shown as the mean log(colony forming units (CFU)/ml) of three biological replicates with error bars corresponding to standard deviations. Light gray bars represent control samples incubated at 30°C for the same time period as test samples. Dark gray bars represent samples incubated for 30 minutes in the presence of 10 mM H2O2 at 30°C. Black bars represent samples incubated for 30 minutes at 45°C. N.D., no colonies detected.