FIG 6.

Effect of cbb₃ oxidases on biofilm formation. Anoxic incubation of P. aeruginosa was performed using 24-well (A and B) or 6-well (C) plates containing LBN medium incubated at 37°C. An AnaeroPack system was used for anoxic static incubation. (A) Time course of the amounts of biofilm formation. The values represent the means ± standard deviations from three independent experiments. The insets show crystal violet-stained biofilms formed at the bottom of 24-well plates. (B) Relative amounts of biofilm formation of NIR mutants at 24 h. The values represent the means ± standard deviations from three independent experiments. *, P < 0.01; **, P < 0.0001 (unpaired two-tailed Student's t test). (C) Three-dimensional images of biofilm structures at 24 h visualized by COCRM. Each projection shows fields of 140 by 140 μm (x-y), as indicated. The insets show the bright-field images of cells scraped from biofilms. Three independent experiments were carried out, and representative images are shown.