Figure 7. Biofilm formation confers stress tolerance in vitro. Standing cultures of the indicated strains (black bars, WT background; grey bars, ΔcprS background) were grown in MH broth with the indicated additions (labels below).

Biofilm formation was impaired by addition of DNase (90 U mL⁻¹). Sub-MIC levels of DOC were included where indicated. Total OD₆₀₀ of three independent cultures, following 2 days growth and resuspension by vortexing was measured. Cultures were normalized to the strain background (WT or ΔcprS) in MH alone. Error bars represent the mean of three biological replicates. NS: not significant **p<0.0001 *p = 0.0018.