Table 1.
Minimum inhibitory concentrations (MICs) of antibiotics against B. subtilis strains. 5 × 105 CFU/mL (OD600 of approximately 0.0005) of B. subtilis liquid cultures were supplemented with increasing concentrations of antibiotics. After 16–20 h in the absence or presence of the antibiotic, bacterial growth was scored by eye. N.A., not available due to the selection markers used for strain construction rendering the strain phenicol resistant; N.D., not determined; PLSA antibiotics that VmlR confers resistance to are highlighted in bold. MICs marked with an asterisk (*) were reported earlier by Brodiazhenko and colleagues (45). Lincomycin MICs for other mutant strains used in this work are summarised in Supplementary Table S1
| MIC, μg/ml | ||||
|---|---|---|---|---|
| Antibiotic | Wild-type 168 | ΔvmlR (VHB5) | vmlR-His6 (VHB223) | ppGpp0 (VHB63) |
| Tiamulin | 80 | 0.3–0.6 | 80 | 20 |
| Retapamulin | 80 | 0.08 | 10 | 1.25 |
| Lincomycin | 80 | 2.5 | 20 | 5 |
| Iboxamycin | 2* | 0.06* | 0.5–1 | 0.25 |
| Virginiamycin M1 | >64 | 2 | 64 | 16 |
| Linezolid | 2 | 2 | 2 | 2 |
| Florfenicol | 3 | 3 | 3 | 3 |
| Thiamphenicol | 8 | 8 | 8 | N.A. |
| Chloramphenicol | 5 | 5 | 5 | N.A. |
| Erythromycin | 0.125 | 0.125 | 0.125 | N.A. |