Figure 7.
The effect of an altered extracellular matrix on gene expression, sporulation, and biofilm architecture. (A) Flow cytometry analysis of PspoIIG-gfp expression as in Figure 2. Wild-type (blue line) and tasA mutant (red line) cells obtained from biofilms harvested at 36 h. Gray peak indicates fluorescence intensity of cells with no fluorescent reporter. (B) Viable spore counts comparing mutants in matrix production (tasA and eps) to wild-type percent of spores in biofilms (black bars) or liquid cultures (white bars). Sporulation was restored by coculturing the different strains with a nonsporulating (sigF) mutant (gray bars). Error bars indicate SEM. (C) Coculturing restores biofilm architecture to matrix-deficient mutants. Top view of biofilms from wild-type, tasA, and eps (top panels) and sigF and cocultures of tasA or eps cells mixed at a 1:1 ratio with a sigF mutant (bottom panels) after 72 h of incubation at 30°C. Bar, 1 cm.