Fig. 6

Quantification of biofilm biomass degradation using CV staining. Staphylococcal strains were allowed to form biofilm in 96-well plates for 24 h. The non-adherent staphylococcal cells were removed, and the established biofilm that adhered to the flat-bottomed 96-well plate was washed twice with PBS before being exposed for 3 h to 0.25×, 0.5×, and 1× MIC of APLss or 1× MIC of Van. The relative percentage of biofilm biomass in the presence of APLss or Van in comparison to the untreated control is shown for (A) MSSA 25923 and (B) MRSA 33591. The data are shown as mean ± SEM. Bars marked with a (*), (**) or (****) indicate statistical significance at the p < 0.05, p < 0.001, and p < 0.0001 levels, respectively. Abbreviations: APLss, antimicrobial peptidase lysostaphin; ns, not significant; Van, vancomycin