Per cell analysis of the probabilistic expression of bcpA.
A) PbcpA-lacZ reporter strain plated on M63 minimal medium agar supplemented with X-gal. B) Confocal microscopy of gfp reporter strains, PbcpA-gfp, PS12-gfp, and E264KmR (vector), cultured overnight in liquid medium. C) Representative flow cytometry analysis of gfp reporter strains, PbcpA-gfp, PS12-gfp, and E264KmR (vector), cultured overnight in liquid medium. The dot plot (top left panel) of side scatter intensity (SS INT) vs. forward scatter intensity (FS INT) shows the events corresponding to B. thailandensis that were gated on (“Gate”) for subsequent analysis. Histograms show the number of GFP-positive events (Count) vs. relative fluorescence intensity (FL1 INT) for each reporter strain, and the percent of GFP-positive bacteria detected in each culture is indicated.