Table 4.
Viability, BacLight staining and ATP levels of germinated B. subtilis spores given no or various treatments.
| Spores analyzed | Viability – cfu/ml (%) | Spores staining green - % (number examined) | ATP levels in pelleted spores - % of total |
|---|---|---|---|
| Initial germinated spores1 | 3.6.•107 +/− 1.4 (100) | 1002 +/− 1.5 (586)3 | 91 +/− 5 |
| Heated germinated spores4,5 | 3.8•105 +/− 1.3 (1) | 0 (404) | nd |
| Germinated spores– control5 | 3.4•107 +/− 1.2 (94) | 95 +/− 3 (638)3 | 89 +/− 5 |
| Germinated spores – bSi4,5 | 3.3•105 +/− 1.4 (0.9) | 0.1 (1843)3 | 10 +/− 5 |
B.subtilis PS533 (wild-type) germinated spores +/− subsequent heat treatment were incubated with or without incubation on control or bSi wafers in duplicate, and spore viability, BacLight staining and ATP levels in pelleted spores and supernatant fluid were determined as described in Methods. Values shown are +/− standard deviations from results in two independent experiments, except for values for ATP levels in and BacLight staining of heated germinated spores.
1These spores were >95% germinated as determined by phase contrast microscopy and 97% germinated as determined by measurement of the DPA released into the pellet and supernatant fractions of the spores after their 1 hr of germination.
2This value has been set at 100% correcting for ~14% of the germinated spores that are stained red (see Fig. 7c) - and all other values are relative to this value.
3~0.8 +/− 0.4% of these spores did not stain at all with the BacLiight reagent are presumably still dormant.
4While these spores retained ~1% viability after heat or bSi wafer treatment, the viable spores are almost certainly dormant spores that have not germinated at the end of the experiment and stain poorly with the BacLight reagent (see Fig. 7c), but can germinate on LB medium agar plates.
5The recovery of spore particles from control and bSi wafers was identical +/− 10% for these three samples.