FIG 4 .

GerG controls Csp levels in mature spores. Western blot analyses of germination regulators in sporulating cells (A) and purified spores (B) from the wild type (WT) (630Δerm-p), the ΔgerG mutant, and the ΔgerG mutant complemented with either gerG (ΔgerG/gerG) or the cspBAC operon (ΔgerG/cspBAC). The Δspo0A mutant was used as a negative control for sporulating cells, since this strain does not sporulate (13); a ΔcspBAC mutant was used as a negative control for analyzing Csp levels in mature spores. CspBA is the primary form detected in sporulating cells, whereas CspB and CspA domains are the primary form detected in mature spores (27). SleC is detected in three major forms: full length (SleC), zymogen (pro-SleC), and proteolytically activated (cleaved SleC [21]). Antibodies against SpoIVA and CotA were used as a loading controls. H.R. represents the heat resistance of each strain relative to the wild type; G.E. refers to the germination efficiency of each strain relative to the wild type. The means and standard deviations shown are based on three biological replicates. Statistical significance relative to the wild type was determined using a one-way analysis of variance and Tukey’s test. ****, P < 0.0001; ***, P < 0.0005; **, P < 0.005; *, P < 0.05.