ALT OprF affects biofilm eDNA levels in TSB. 24-h static microtiter PAO1 (black), ΔpslD (blue), and ΔoprF (red) biofilms grown in TSB (A), LB (B), or TSB (C) with 10 g/L NaCl were stained with the eDNA-specific dye DiTO-1. Fluorescence intensity from each strain was normalized to respective biofilm cell numbers (via absorbance at OD600). Error bars, SEM (n = 3); dot, each biological replicate, which is the average of 5 technical replicates; letters, statistical groupings (P < 0.05, one-way ANOVA with post hoc Tukey HSD).