FIG 5.

RscS is critical for pABA-stimulated ES114 biofilms. (A) Colony biofilm formation was evaluated following growth on TPC of the following strains: WT (ES114), ΔrscS (KV10130), ΔrscS+rscS (KV10166), ΔsypF+sypF-hpt (KV7226), and ΔrscS ΔsypF+sypF-hpt (KV9953). Pictures were taken using a Zeiss Stemi 2000-c microscope with ×6.5 magnification at 72 h before and after disruption using a toothpick. Pictures are representative of three separate experiments. Arrows indicate where “pulling,” indicating cohesion, was observed. Dotted arrows represent where “pulling” was observed but to a lesser extent, with portions of the colony breaking off during disruption. (B) Colony biofilm formation was evaluated following growth on TPC of the following strains: sypG-D53E (sypG*; KV6527), ΔrscS+sypG* (KV10391), ΔsypE+sypG* (KV10444), and ΔrscS ΔsypE+sypG* (KV10442). Pictures were taken using the Zeiss Stemi 2000-c microscope with ×6.5 magnification at 72 h before and after disruption using a toothpick. Pictures are representative of 3 separate experiments. Arrows indicate where “pulling,” indicating cohesion, was observed. Dotted arrows represent where “pulling” was observed but to a lesser extent, with portions of the colony breaking off during disruption. For both sypG* ΔsypE derivatives (with or without an intact rscS), the colony biofilms were adherent to the plate and were not perturbable using the toothpick assay. (C) Biofilm cohesion was quantified from images as described in Materials and Methods with scores of 1 assigned to a null phenotype and 4 to the most/strongest. Statistics for panel C were performed via a one-way ANOVA using Tukey’s multiple-comparison test, where biofilm strength was the dependent variable. **, P < 0.0094; ***, P = 0.0003; ****, P < 0.0001.