TABLE 3.
Efficiency of sporulation in ethanol-treated and untreated wild-type, sinR, and rapA strainsa
| Strain | SSM
|
SSM + ethanol (0.7 M)
|
||||
|---|---|---|---|---|---|---|
| Viable cells/ml | Spores/ml | Spores (%)b | Viable cells/ml | Spores/ml | Spores (%)b | |
| JH642 (wild type) | 4.0 × 108 | 3.6 × 108 | 90.00 | 3.0 × 107 | 1.7 × 104 | 0.057 |
| RG23 (rapA) | 1.9 × 108 | 1.8 × 108 | 94.74 | 2.7 × 107 | 3.4 × 106 | 12.59 |
| RG19 (sinR) | 8.0 × 108 | 7.5 × 108 | 93.75 | 2.8 × 107 | 5.2 × 106 | 18.57 |
| RG433 (sinR rapA) | 8.3 × 108 | 8.1 × 108 | 97.59 | 1.3 × 107 | 1.2 × 107 | 92.31 |
a
Cultures were grown in SSM at 37°C for 20 h. For the treated cultures the alcohol (0.7 M) was added 2 h before the onset of stationary phase. The results of a representative experiment are shown.
b
Note that the ethanol-treated culture of strain RG433 (sinR rapA mutant) reached the same sporulation efficiency as those of the untreated cultures (bold numbers).