Function of BriC peptide in the pneumococcal competence and virulence portfolio
Fig 9
ComAB plays a role in the export of BriC.
(A) Representative confocal microscopy images showing top view of the reconstructed biofilm stacks of WT, ΔcomE, ΔcomE::PbriClong-briC and ΔcomEΔcomAB::PbriClong-briC cells of strain R6D stained with SYTO59 dye at 72h. Images are pseudo-colored according to depth (scale shown). (B) COMSTAT2 quantification of 72h biofilm images. Y-axis denotes units of measurement: μm3/μm2 for biomass, and μm for maximum thickness and average thickness over biomass. Error bars represent standard error of the mean calculated for biological replicates (at least n = 3). (C) Extracellular Nano-Glo HiBiT activity of the BriC reporter produced by WT and ΔcomAB cells (whole cells). The HiBiT activity was measured by recording luminescence with an integration time of 2000 milliseconds. Error bars represent standard deviation calculated for biological replicates (n = 3); “ns” denotes non-significant comparisons, *** p<0.001, and **** p<0.0001 using ANOVA followed by Tukey’s post-test.