Fig. 2

a Top view of biofilm architecture from wild type, tasA and tasA/sinR strains with negative (left panels) and positive expression of TasA-mCherry (right panels) after 72 h of incubation. A magnification of the edges of the colony is presented at the right of each the whole colony top view picture. Scale bar is 1 cm. b Immunoblotting of biofilm extracts from wild type (lane 1), sinR (lane 2), tasA::TasA-mcherry (lane 3) and tasA/sinR::TasA-mCherry (lane 4) strains; TasA and TasA-mCherry were detected using specific anti-TasA (upper panel) and anti-dsRed2 (lower panel) antibodies. The red arrows indicate the position of TasA and TasA-mCherry. The red bracket indicates an anti-TasA reactive band with a lower molecular weight of TasA, presumably TasA degradation. The molecular weights (kDa) of the proteins are indicated. c Red fluorescence quantification of 24, 48 and 72 h biofilms. Data is presented as the mean ± SEM of four independent experiments. Asterisks denote significant differences in TasA-mCherry red fluorescence between tasA and tasA/sinR strains expressing TasA-mCherry (t test, **p < 0.001, n ≥ 4). d Viable spore counts comparing sinR, tasA::TasA-mCherry and tasA/sinR::TasA-mCherry to wild type percent of spores in biofilms. Error bars indicate SEM (t-test, *p < 0.05, n = 4)