FIG 5.

SigB regulates sinR expression. (A) β-Galactosidase activity from the sinR-lacZ::amyE reporter fusion in wild-type and isogenic ΔsigB cells grown in static LBY. Typical output from one of four independent experiments is shown. (B to D) SinR and SigB do not generate additive effects on biofilm growth. Fifty-hour-old representative biofilms developed by standing cultures of the wild type (strain JH642) and isogenic mutants with altered SinR (ΔsinR, strain RG432) and/or SigB (ΔsigB ΔsinR, strain RG5578) activity. Biofilm mass was measured using the crystal violet technique, as indicated. Similar results were observed in several independent experiments. (E) Rate of biofilm formation by the wild type and different isogenic mutants with altered SigB, SinR, and SigB-SinR activities. Each data point in panels A and E is an average ± SEM from five independent representative experiments.