FIG 7.

Effects of various host-related stresses on the P_carRS activity. (A to D) The V. vulnificus strains carrying reporter plasmid pDH2207 with P_carRS fused to promoterless luxCDABE were grown to an A₆₀₀ of 0.5 and further incubated for 120 min with (+) or without (−) stresses as follows: PMB, 1 μg mL⁻¹ (A); CaCl₂ or MgCl₂, 10 mM (B); bile salts, 0.03% (wt/vol) (C); acidic pH (pH 5.7) (D). The cellular luminescence and growth (A₆₀₀) were measured at time intervals as indicated. RLU was calculated by dividing the luminescence by the A₆₀₀. Error bars represent the SD from three independent experiments. RLU, relative luminescence unit; WT, wild type carrying pDH2207; ΔcarR, carR mutant carrying pDH2207; ΔcarS, carS mutant carrying pDH2207.