FIG. 1.

Inhibition of biofilm formation by the iron chelator dipyridyl. (A) Wild-type strain was grown in increasing amounts of 2,2′-dipyridyl. (B) Wild-type strain was incubated in LB or LB with 200 μM 2,2-dipyryidyl. Increasing concentrations of ferric chloride or magnesium chloride were added to the dipyridyl-containing samples. Strains were grown at 25°C for 24 h in LB. Final planktonic growth was recorded at 600 nm (light gray bars). After washing, staining with crystal violet, and solubilization, final biofilm formation was recorded at 570 nm (dark gray bars). The average of triplicate experiments is shown.