Fig 3.

Effects of the absence of the GerA or GerK GRs and overexpression of the GerA or GerB* GRs on the rate of l-asparagine germination via the GerB* GR. Spores of various strains were prepared, purified, and germinated with various l-asparagine concentrations. Germination was measured by monitoring DPA release, and rates of DPA release were determined as described in Materials and Methods. The rate of germination of FB10 spores (gerB*) with 10 mM l-asparagine was defined as 100%. The symbols used for the spores of the various strains are as follows: (A) ○, FB10 (gerB*); ●, PS3521 (ΔgerA gerB*); ▵, PS3665 (ΔgerA gerB* ΔgerK); and ▲, PS3501 (↑gerA gerB*); and (B) ○, FB10 (gerB*); ●, PS3502 (↑gerB*); and ▵, PS3415 (↑↑gerB*). All rates shown are averages of results from at least duplicate measurements with at least two different spore preparations, and differences in relative germination rates were ≤15%. In panel A, the differences in germination rates at ≥0.3 mM l-asparagine between FB10 spores and ↑gerA and ΔgerA ΔgerK spores were significant (P < 0.01), but the differences between the germination rates of FB10 and ΔgerA spores were not (P < 1). In panel B, the differences in germination rates at ≥0.5 mM l-asparagine between FB10 spores and ↑gerB* or ↑↑gerB* spores were significant (P < 0.008).