Resistance of <i>P</i>. <i>stuartii</i> and <i>P</i>. <i>stuartii ΔP2</i> cells to high concentrations of urea and to pH variations.

<p>Effect of urea (A and E) and pH (C and G) on bacterial growth, as judged from the O.D. of cultures at 600 nm. The impact on biofilm genesis, attachment and consolidation was evaluated by adding urea (B and F) or changing the pH (D and H) during the lag, stationary and preformed biofilm phases, respectively. Biofilm formation was quantified 24 h later, by PrestoBlue staining. Fluorescence values were normalized with respect to the control wells containing no urea and buffered at pH7.