FIG 7.

FNLLGLLA_01127 represses biofilm formation in a microfermentor. (A) Results of 96-well plate biofilm assay after 24 h of growth in BHLC corrected by optical density at 600 nm (0D₆₀₀) after 24 h growth in plate. The mean value for the WT is adjusted to 100%. Min-max box plots of 6 biological replicates for each strain are shown, and each replicate is the mean of two technical replicates. *, P < 0.05 (Mann-Whitney test). (B) Aggregation curve in a spectrophotometry cuvette. A value of 100% represents lack of aggregation, and 0% represents complete sedimentation of the culture. Medians of 6 biological replicates are shown, and error bars represent 95% confidence interval. *, significant by Mann-Whitney test, corrected for multiple testing with Bonferroni correction; significance is achieved if the P value is <0.007. (C) Biofilm formation in a continuous-flow microfermentor on a glass spatula during 48 h in BHILC. The mean value for the WT is adjusted to 100%. Min-max box plots of 4 biological replicates for each strain are shown. *, P < 0.05; **, P < 0.005 (Mann-Whitney test). A picture of a spatula before resuspension is shown for each strain below the histogram. (D) Biofilm formation in a continuous-flow microfermentor on a glass spatula during 48 h in BHILC plus chloramphenicol. The mean value for WT+pEmpty is adjusted to 100%. Min-max box plots of 4 biological replicates for each strain are shown. *, P < 0.05 (Mann-Whitney test). A picture of a spatula before resuspension is shown for each strain below the boxplot. (E) Scanning electronic microscopy of Δ1127 biofilm grown under continuous flow of BHILC in a microfermentor on a plastic microscopy slide. Magnifications, ×2,000 and ×5,000. (F) Initial adhesion on glass spatula. The percentage of CFU that adhered to the spatula in 30 min, controlled by the number of CFU of the inoculation solution, is shown. Min-max box plots of 6 to 9 replicates per strain are shown. *, P < 0.05 (Mann-Whitney test); ns, not significant.