TABLE 2.
Streptonigrin resistance of L. pneumophila strainsa
| Streptonigrin (μM) | Mean growth (107 CFU/ml) ± SD
|
|
|---|---|---|
| 130b | NU269 | |
| 0 | 106.67 ± 12.58 | 105.33 ± 24.70 |
| 0.75 | 16.07 ± 0.72 | 48.67 ± 7.77 |
| 1.5 | 0.33 ± 0.21 | 8.33 ± 6.11 |
a
Bacteria were resuspended to 109 CFU/ml, and dilutions were plated on BCYE agar containing no iron supplementation and either 0, 0.75, or 1.5 μM streptonigrin. Data show the mean and standard deviation (n = 3). This experiment was performed in duplicate with similar results. Significant differences were noted between the wild type and the feoB mutant when plated on agar containing 0.75 μM streptonigrin (Student's t test, p < 0.01).