FIG. 5.

Modulation of biofilm formation via RExBAD-mediated control of F′ factor conjugative pilus synthesis. The abilities of the different strains to form biofilms in microfermentors were determined by using M63B1 medium containing 0.4% glucose with or without increasing concentrations of arabinose. After 24 h, microfermentor and spatula images were captured (A), and the biofilms formed on the glass spatulas were resuspended in 10 ml of M63B1 medium to obtain OD₆₀₀ measurements (B). In panel A the results of a representative experiment in which no arabinose or 0.04% arabinose was added are shown. In panel B, the histograms show the results based on averages for three independent experiments in which the OD₆₀₀ of wild-type strain TG1 grown in LB medium without added sugar was defined as 100%. Ø indicates that no arabinose was added.