Figure 3.

Growth complementation of E. coli ΔrelAΔspoT on minimal medium plates by heterologous expression of C. glutamicum genes rel_Cg, relS_Cg, relP^*_Cg or relP_Cg. The parental strain E. coli MG1655 and E. coli ΔrelAΔspoT each containing the empty vector pBAD24 were used as a positive and negative control, respectively. All strains were cultivated using initial OD₆₀₀ values of 0.05 in LB-Medium containing 0.001% arabinose for 3 h. The cells were washed and serially diluted in PBS-buffer. 5 μL aliquots of every strain and dilution stage were spotted on minimal medium plates with 0.4% glycerol as carbon source and different arabinose concentrations. Incubation was carried out at 37°C for 48 h.