FIG 5.

Static biofilm formation by S. aureus. Static biofilms were grown in chambered cover glass plates at 37°C for 12 h. Z-stacks were obtained with CLSM at 2-μm intervals, reconstructed with Zeiss ZEN 2012 software, and analyzed with Imaris 7.0 software. All confocal parameters were set with the settings for NCTC8325 pGFP biofilm as standard settings for comparing the biofilms produced by ΔmgrA pGFP, Δα/β pGFP, and ΔmgrA/α/β pGFP strains. (A) Biofilm images of S. aureus strains. Biofilm images were obtained in at least 10 randomly chosen fields of the same biofilm. Extensions and scales are the same in all images (total extension on the x axis, 170 μm; total extension on the y axis, 170 μm). (B to E) Biofilm quantitation. Biofilm parameters were measured at 12 h in at least 15 randomly chosen biofilm CLSM images of the same extension. Horizontal bars depict the means. Statistical analysis was performed with t tests. ns, P > 0.05; ***, P < 0.001; ****, P < 0.0001. NCTC8325 pGFP, NCTC8325 WT strain carrying plasmid pGFP; ΔmgrA pGFP, mgrA mutant strain carrying plasmid pGFP; Δα/β pGFP, psmα psmβ double mutant strain carrying plasmid pGFP; ΔmgrA/α/β pGFP, mgrA psmα psmβ triple mutant strain carrying plasmid pGFP.