Fig. 1

CssR was involved in stress resistance. a The growth (OD₆₀₀) of the WT(pXMJ19) (C. glutamicum RES167 parental strain with the empty plasmid pXMJ19), ΔcssR(pXMJ19) (the mutant lacking cssR with the empty plasmid pXMJ19), and ΔcssR(pXMJ19-cssR) (the ΔcssR mutant expressed the wild-type cssR gene with a shuttle vector pXMJ19) strains after 24 h at 30 °C in LB broth medium containing 0.3 μg ml⁻¹ gentamicin (GEN), 1.1 μg ml⁻¹ erythromycin (ERY), 0.4 μg ml⁻¹ ciprofloxacin (CIP), 40 μM cadmium chloride (CdCl₂), 2 mM nickel sulfate (NiSO₄), 0.1 mM potassium dichromate (K₂Cr₂O₇), 50 mM hydrogen peroxide (H₂O₂), 5 mM diamide, 0.3 mM cumene hydroperoxide (CHP), and 1.5 mM tet-butyl hydroperoxide (t-BHP), respectively, was recorded. The growth in LB broth medium without agents was used as control. b The WT(pXMJ19), Δncgl1576-ncgl1577(pXMJ19) (the mutant lacking ncgl1576-ncgl1577 with the empty plasmid pXMJ19), and Δncgl1576-ncgl1577(pXMJ19-ncgl1576-ncgl1577) (the Δncgl1576-ncgl1577 mutant expressed the wild-type ncgl1576-ncgl1577 gene with a shuttle vector pXMJ19) strains grown to the stationary phase were exposed to indicated agents for 60 or 30 min at 30 °C, respectively. The viability of the cells was determined. Data shown were the averages of three independent experiments, and error bars indicated the SDs from three independent experiments. *P < 0.05; **P < 0.01; ***P < 0.001. n.s. no significance