Fig. 1

Growth of C. glutamicum RES167 parental strain containing the high copy number of empty plasmid pXMJ19 (WT), ΔmstX mutant (strains lacking mstX gene contained empty pXMJ19) and the complementary strains ΔmstX⁺ (ΔmstX mutant was complemented with plasmids carrying the wild-type mstX gene) in LB broth with 0.25 μg ml⁻¹ neomycin (b), 0.2 μg ml⁻¹ vancomycin (c), 0.05 μg ml⁻¹ gentamycin (d), 24 μg ml⁻¹ azithromycin (e), and 110 μg ml⁻¹ Lincomycin (f). Bacterial growth was monitored by the optical density at 600 nm for up to 24 h after addition of the same cell density of exponentially grown culture in aerobic condition. Growth of the three strains in LB broth without antibiotic was used as control (a). Mean values with standard deviations (error bars) from at least three repeats were shown. ***P ≤ 0.01; **P ≤ 0.01; *P ≤ 0.05