FIG. 2.

(A) Comparison of the wild-type Sterne strain and that strain transformed with pPS12 during vegetative growth in TSB over time (mean of three independent experiments shown with error bars to indicate ± 1 standard deviation). (B) Kinetics of germination of spores from the parent strain, the parent strain transformed with pYS-NSB, and the germination reporter strain. Spores were grown in 5% BHI broth, and samples were heat treated to inactivate vegetative cells at the time points shown. Colony counts following heat treatment represent the numbers of heat-resistant spores. The difference between the spore counts at the starting point (t₀) and those at subsequent test points (t_x) indicates the number of spores that germinated at each time point (error bars represent variations among three like samples at each time point ± 1 standard deviation). The germination curves for three individual experiments are shown. The level of sspBp::lux reporter germination at 60 min (in red) is statistically lower than for the wild type (in black) (P < 0.001), as well as for the wild type with vector alone (in blue) (P < 0.001). There is also a difference in germination at 60 min between the wild type (black) and the wild type with vector alone (blue) (P = 0.016).