FIG. 4.

The kinetics of biofilm formation for B. parapertussis. The wt strain 12822 was grown in SS medium either in the absence (black bars) or presence (white bars) of the modulator MgSO₄. The OD₅₄₀ of solubilized crystal violet from surface-attached cells grown in microtiter plates and assayed at specified time-intervals is shown. Each data point is the average for six wells, and error bars indicate the standard errors. Representative data from one of at least three independent experiments are shown.