FIG. 7.

Ability of wild-type and mutant strains to form biofilms. Wild-type and mutant strain biofilms were formed in LB medium supplemented with 3% NaCl at 28°C for 20 h. Bacteria attached to borosilicate glass tubes were removed by washing five times with distilled water and then stained with crystal violet. The optical density at 570 nm was measured to quantify the amount of dimethyl sulfoxide-solubilized dye. Data shown are the averages of three independent experiments. Error bars represent standard deviations.