FIG 2.

Swimming motility assays of the P. aeruginosa wild type (WT) and strains carrying inactivated genes for various enzymes of denitrification. (A) Soft agar plates containing arginine as energy source were point inoculated with overnight cultures of the strains to be tested, incubated anaerobically at 37°C for 5 days, as described in Materials and Methods. (B) The diameters of the halos of bacterial growth, representing the distance migrated by the strain via swimming, were measured. The plots show the mean halo diameters from triplicate measurements and their standard deviations.