Figure 4

Promoter activity ompC , F , X and R under different concentrations of NaCl. The lacZ fusion reporter plasmid for each of ompC, F, X, and R was transformed into WT or ΔompR to determine the β-galactosidase activity (miller unites), respectively. Bacterial cultures in the LB broth (0.5% yeast extract, 1% tryptone and 1% NaCl) at the middle exponential growth phase (an OD₆₂₀ of about 1.0) were diluted 1:50 into the fresh LB broth. Bacterial cells were grown at 26°C to an OD₆₂₀ of about 1.0, pelleted and resuspended in the fresh LB broth containing 0, 0.4, 0.6, 1, 3 and 6% NaCl, respectively, and allowed to continue growing at 26°C for 20 min for bacterial harvest.