FIG. 2.

β-Galactosidase activities in P. aeruginosa wild type (gray bars) and the Δanr mutant (black bars) containing the respective P_uspL-lacZ, P_uspM-lacZ, P_uspN-lacZ, and P_uspO-lacZ fusions during anaerobiosis. Strains were grown aerobically at 37°C in LB medium to an OD₅₇₈ of 0.7 (time point 0) and transferred to anaerobic conditions. Since the medium contained no alternative electron acceptor, the shift to anaerobic conditions resulted in a growth arrest for 4 h. Aliquots after 15, 30, 60, and 180 min were taken for β-galactosidase assays. All experiments were repeated three times; standard deviations are indicated.