FIG 4.
Fraction of nfxB mutants in the 72-h-old PAO1 flow cell biofilm population at different time points of CIP treatment. Shown are the fractions of biomass expressing gfp in 72-h biofilms formed by PAO1-mCherry-PCD-gfp+ and PAOΔnfxB-mCherry-PCD-gfp+ at different time points of treatment with CIP. The positive control had significantly higher biomass with green fluorescence at time zero (*, P < 0.0001) and at 48 h (**, P = 0.01) than that of the wild type. After 72 h and 96 h of CIP treatment, the fraction of green fluorescent biomass in the PAO1-mCherry-PCD-gfp+ (representing nfxB mutants) biofilm approaches that of the positive control PAOΔnfxB-mCherry-PCD-gfp+.