Table 2.
Activity of spectinamides against various mono-resistant typed M. tuberculosis strains
| Strain | Resistance | MIC (μg/ml) | ||||||
|---|---|---|---|---|---|---|---|---|
| 1329 | 1443 | 1445 | 1544 | 1599 | Spec | Strep | ||
| H37Rv | None | 1.6 | 0.8 | 1.6 | 1.6 | 1.6 | 100 | 1.6 |
| ATCC 358221 | Isoniazid (katG S315T) | 3.1 | 1.6 | 3.1 | 1.6 | 1.6 | 100 | 1.6 |
| ATCC 35820 | Streptomycin (rpsl K43R) | 3.1 | 1.6 | 6.3 | 1.6 | 1.6 | 200 | >200 |
| ATCC 358382 | Rifampin (rpoB S351L) | 1.6 | 6.3 | 0.8 | 1.6 | 1.6 | 100 | 1.6 |
| ATCC 358373 | Ethambutol | 3.1 | 1.6 | 6.3 | 1.6 | 1.6 | 100 | 1.6 |
| H37Rv-HL-144 | 1329 | >200 | >200 | >200 | >200 | >200 | >200 | 1.6 |
| H37Rv-HL-154 | 1329 | >200 | >200 | >200 | >200 | >200 | >200 | 1.6 |
Abbreviations: MIC, minimum inhibitory concentration; Spec, spectinomycin; Strep, streptomycin.
1
Isoniazid MIC = >12.5μg/ml;
2
Rifampin MIC = >25.0 μg/ml;
3
Ethambutol MIC = >25.0 μg/ml.
4
Representative spontaneous spectinamide-resistant mutants with base changes in 16S rRNA were not cross-resistant to linezolid, capreomycin, streptomycin, kanamycin, isoniazid, ethambutol, and rifampicin. MICs were determined using method 1.