Figure 3.

Streptococcal viability on biofilms formed on human fibrinogen. (A) Viability of NEM316 wild-type (WT) and NEM316 deleted for saeR (ΔsaeR) strains on twelve-well plates coated with human fibrinogen (hFg). Biofilms at 48 h were detached with trypsin (1 mg/mL) and disaggregated by vigorously pipetting to enumerate colony forming units (CFUs) of WT and ΔsaeR strains. Results are means ± SD from three independent experiments performed in triplicate. * p < 0.05, as determined by Mann–Whitney statistical analysis; (B) fluorescence images of 48-h-old GBS biofilms on hFg. WT and ΔsaeR biofilms were incubated with orange acridine (OA), with viable and dead cells staining in green and red, respectively. Shown are representative images of three independent experiments. Scale bar = 10 µm.