Effect of increased <i>ahpC</i> expression on biofilm formation.

<p>Biofilm formation levels were determined with crystal violet staining after 24 h incubation of samples. The results show the means and standard deviations of a representative experiment with triplicate samples. The experiment was repeated six times and all produced similar results. The statistical differences between the wild type and each mutant were determined by <i>t</i>-test. NS: non-significant, *<i>P</i>≤0.05, **<i>P</i>≤0.01, ***<i>P</i>≤0.001, ****<i>P</i>≤0.0001.