FIG 2.

Germination and outgrowth of spores of different B. subtilis strains. (A to C) Dormant spores of the wild-type (WT) (●), nfo exoA (◆), nfo exoA disA (■), and nfo exoA disA amyE::PsspB-disA (▲) strains were heat shocked and germinated, and spore germination and outgrowth were measured by monitoring the OD₆₀₀ of the cultures, as described in Materials and Methods. Values are averages ± standard deviations for triplicate determinations in three separate experiments (with different batches of spores). (D and E) Outgrowth (D) and germination (E) of spores of different strains. (D) Germinated spores of the wild-type (●), nfo exoA (■), and nfo exoA disA (◆) strains separated from dormant spores on a Nycodenz density gradient were inoculated into 2× SG medium, and outgrowth was monitored by determining the culture's OD₆₀₀, all as described in Materials and Methods. Values are averages ± standard deviations for duplicate determinations in two separate experiments (with different batches of spores). (E) Dormant spores of wild-type (WT), nfo exoA, and nfo exoA disA strains were heat shocked and then germinated in 25 mM Tris-HCl buffer (pH 7.4) with 10 mM l-alanine, and germination was monitored by determining the culture's OD₆₀₀, all as described in Materials and Methods. The results are representative, and the experiment was performed at least two times with different batches of spores, all of which gave similar results.