FIG 2.

Competitive dynamics of PAO1 and PA14 with altered piliation or matrix production capacity. This figure reports the change in frequency of WT PAO1 and the PAO1 Δpsl mutant in coculture biofilms with WT PA14 as well as the change in frequency of WT PAO1 in a dual-strain biofilms with PA14ΔpilU, PA14 ΔbifA, and Pel-overproducing strains (Pel O/E) supplemented with arabinose. Biofilms were inoculated with a 1:1 mixture of each strain pair (n = 9 to 18 nonoverlapping image stacks from 4 to 6 separate microfluidic chambers). Error bars denote the standard deviations; Wilcoxon signed-rank tests with Bonferroni correction were used for pairwise comparisons; *, P < 0.05; all other comparisons were not significant.