Flow cytometry analysis of dormant and germinating spores of the wild type and gerE, spsA, and sps mutant strains. Dormant spores, non-heat-activated spores without Syto 16. T0, heat-activated spores with Syto 16 but no germinants. T2.5 to T20, time points (in minutes) after the addition of germinants (L-Ala-GFK). The dotted lines in each panel separate germination-unspecific (on the left) and germination-specific (on the right) fluorescence. The experiment was repeated three times with independent spore preparations and always gave similar results.