FIG. 3.

Germination of spores over long periods in liquid medium. Spores (0.1 OD₆₀₀ unit/ml) from the wild-type strain PS832 (□) and the mutant strain FB85 (○) were inoculated into 5 ml of LB medium supplemented with ampicillin (40 μg/ml) and incubated at 37°C. An aliquot was withdrawn every 24 to 48 h for 20 days, heated at 70°C for 1 h, diluted, plated on LB agar, and incubated at 37°C for 24 h prior to colony counting. The titer (expressed as a percentage of the titer on day 0, which was 1.25 × 10⁸ CFU/ml/OD₆₀₀ unit for wild-type spores and 5 × 10⁵ CFU/ml/OD₆₀₀ unit for mutant spores) was plotted against the period of incubation in liquid medium.