Fig. 3: Cell-surface hydrophobicity, motility, biofilm formation, adhesion to host cells, and in vivo virulence of ompA-like mutants.

A Representative microscopic images (40×) of bacterial cell aggregation of mutants and WT after exposure to increasing concentrations of ammonium sulfate. B Representative images of surface-associated motility of each mutant and WT assayed on semisolid (0.25%) LB agar plates. C Amount of biofilm formed by each mutant and WT (n = 30), as measured by crystal violet stain in a 96-well tissue culture plate. D Adhesion of each mutant and WT to human A549 lung epithelial cell monolayers infected using a MOI of 10. Cell-surface-adherent bacteria were enumerated after 2.5-h incubation (n = 3). Data are shown as means ± SDs. Statistical significance was evaluated by one-way ANOVA. E In vivo, virulence was assessed in G. mellonella larvae peritoneally injected with 10⁵ CFU and scored for mortality over 96 h (n = 40). In this panel, statistical significance was evaluated with a Log-rank Mantel–Cox test: *p < 0.05, **p < 0.01, ***p < 0.001, and ****p < 0.0001, vs WT strain; °p < 0.05, and °°°p < 0.001.