Architecture of <i>B. subtilis</i> communities.

<p>(A) Three-dimensional projection of <i>B. subtilis</i> 168 GFP and ND_medical GFP biofilms obtained from xyz confocal images series using IMARIS software. Images present an aerial view of biofilm structure with the virtual shadow projection on the right. Scale bar correspond to 50 µm. (B) SEM images of 24 h-biofilms. (C) Dye binding properties of <i>B. subtilis</i> macrocolonies grown for 72 h on Congo red indicator plates.</p

Real-time visualization of PAA (0.05%) activity in B. subtilis biofilms.

<p>(A) Quantification of Chemchrome V6 fluorescence intensity in B. subtilis 168 (white squares) and ND_medical (black squares) biofilms during PAA treatment at 500 ppm. Values shown corresponds to the average of the fluorescence at five depths with standard deviation in the biofilm for a representative experiment. Inactivation rate k_max was obtained after fitting GinaFIT “log linear + tail” inactivation model on experimental data. The means of three experiments ± standard deviation are presented in the inset. (B) Visualization of Chemchrome V6 fluorescence loss (membrane permeabilisation) in B. subtilis 168 and ND_medical biofilms at 0. 15 and 30 secondes and 0. 5 and 10 minutes respectively during PAA treatment (0.05%). Each image corresponds to the superimposition of a green fluorescence image of a representative experiment on a greyscale image of initial fluorescence at the same location. Scale bars correspond to 20 µm.</p

Bactericidal activity of water and 0.35% PAA on single and mixed species biofilms after 5 min of treatment.

<p>Data shown are mean of three experiments ± standard deviation. Samples from which no survivor were recovered are represented by (−). Minimum detection of 2 logs CFU/well.</p

Strains used in this study.

a<p><i>spec</i> and <i>ery</i> stand for spectinomycin and erythromycin resistance markers respectively.</p

Architecture of <i>S. aureus</i> AH478 mCherry biofilm and <i>B. subtilis</i> ND_medical GFP/<i>S.aureus</i> AH478 mCherry mixed biofilm.

<p>(A) 3D reconstruction of <i>S.aureus</i> AH478 mCherry biofilms.(B) 3D reconstruction and section at higher magnification of mixed species biofilm of <i>B. subtilis</i> ND_medical GFP (green)/<i>S.aureus</i> AH478 mCherry (red). Scale bars correspond to 20 µm.</p