FIG 2.
β-Galactosidase activities of transcriptional fusions PlasR-′lacZ (A and B), PrhlI-′lacZ (C and D), and PrhlR-′lacZ (E and F). Shown is the ratio of expression in parental PAO1 (A, C, and E) or PA14 (B, D, and F) versus expression in the reference strain. Results were obtained after 6 h of growth at 37°C with aeration. Glucose (glu) and arabinose (ara) were added in the culture medium after 1 h 30 min of growth at a final concentration of 0.5%, allowing, respectively, repression or induction of the PBAD promoter of pTS51 bearing qslA. **, P < 0.01; *, P < 0.05. NS, not significant.