TABLE 4.
Frequency of rifampin resistance in E. coli tester strain CC104
| Strain, compound, and concn (μg/ml)a | Survivalb | Rifr frequency (per 108)c | Fold |
|---|---|---|---|
| CC104 | |||
| Nitazoxanide | |||
| 0 | 1 | 4.8 | |
| 5 | 1 | 6.7 | |
| 10 | 1 | 2.6 | |
| CC104(pGS950) | |||
| Nitazoxanide | |||
| 0 | 1 | 7.0 | |
| 5 | 1 | 5.5 | |
| 10 | 1 | 6.3 | |
| CC104 | |||
| Nitrofurazone | |||
| 0 | 1 | 3.36 | |
| 1 | 1 | 26.4 | 7.9 |
| 2 | 0.7 | 58.6 | 17.4 |
| 5 | 10−3 | 75.4 | 22.4 |
| Nitrofurantoin | |||
| 0 | 1 | 3.36 | |
| 1 | 0.9 | 6.14 | 1.8 |
| 2 | 0.9 | 8.59 | 2.6 |
| 5 | 2.5 × 10−2 | 32.58 | 9.7 |
| Furazolidone | |||
| 0 | 1 | 3.36 | |
| 0.1 | 10−2 | 64.0 | 19 |
| 1 | 10−3 | 0 | |
| Controld | |||
| Metronidazole | |||
| 0 | 1 | 0.75 | |
| 5 | 10−2 | 53 | 70 |
| 10 | 10−4 | 378 | 504 |
a
The bacteria (E. coli CC104 + pBSK or CC104 + pGS950rdxA+) were grown on LB agar with the appropriate concentration of drug and then plated on medium containing rifampin as indicated in the text.
b
EOP − efficiency of plating (EOP of 1 = no loss of viability).
c
The Rifr frequencies represent the means of three determinations and are reported as the number of Rifr colonies per 108 bacteria plated.
d
Similar to data of Sisson et al. (29); included for comparison. Control, CC104(pGS950).