TABLE 6.
Suppression of antibiotic sensitivity and relative AcrA levels
| Relevant strain characteristic(s) | Zone of inhibition (mm) in presence of antibiotica
|
Relative AcrA levelb | |||
|---|---|---|---|---|---|
| Novobiocin (30 μg) | Erythromycin (15 μg) | Rifampin (5 μg) | Vancomycin (75 μg) | ||
| TolCR367HacrAB+ | 10.0 | 11.4 | 18.5 | 19.0 | 1.00 |
| TolCR367Hacr::IS2 | 8.1 | 8.3 | 17.8 | 19.0 | 2.38 |
| TolCR367Hacr6-2 | 7.8 | 7.4 | 17.0 | 20.3 | 2.15 |
| TolCR367H ΔacrR::Kmr | 8.5 | 9.7 | 18.3 | 18.0 | 1.69 |
| TolCR367H(pACYC184) | 11.3c | 11.4 | 18.8 | 17.8 | 1.16 |
| TolCR367H pacrAB+ | 7.9 | 7.5 | 17.8 | 20.6 | 6.47 |
a
The diameter of the paper disks was 6.5 mm. Averages from three independent experiments are shown.
b
AcrA levels were determined from whole-cell extracts by Western blot analysis.
c
The presence of pACYC184 vector DNA consistently increased the sensitivity to novobiocin.