Quantification of the biofilms produced by different <i>L. monocytogenes</i> strains.

<p>(A) Microtiter plate assay: Biofilm was measured each day for cells inoculated in TSB broth with 96-well microtiter plate for 7 days. The experiments were repeated three times and error bars indicate the standard deviations. The T-test was used to calculate the <i>p</i>-value between the wild-type and mutants. (B) Microscope assay with 0.1% FITC. I: wild-type <i>L. monocytogenes 4b G</i>; II: <i>Δ</i>1771; III: <i>Δsod</i>; VI: <i>Δ</i>1771<i>Δsod</i>. Cells from each strain for this method were incubated on glass slides for 3 days to form biofilms.