FIG 6.

Multicopy expression of rscS induces biofilm formation on medium containing pABA/calcium. (A) Colony biofilm formation was assessed following growth on tTBS (T), TC, TP, and TPC of the following strains: ES114/pKV69 (vector control) and ES114/pLMS33 (wild-type rscS on a plasmid; pRscS). Pictures were taken using the Zeiss Stemi 2000-c microscope (×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) 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 two-way ANOVA using Tukey’s multiple-comparison test, where biofilm strength was the dependent variable. *, P = 0.0170; **, P < 0.0071; ****, P < 0.0001.