Table 5.
Molecular MIC analysis of avirulent Y. pestis Kim53pCD1−pPCP1− isolates with reduced doxycycline susceptibility.
| Normalized FCa |
||||
|---|---|---|---|---|
| Doxycycline (μg/ml) | Parentalb | #36b | #36-4b | #36-4-18b |
| 0.125 | 70 ± 64 | 1.2 ± 0.8 | 2.8 ± 0.3 | 1.9 ± 2.2 |
| 0.25 | 117 ± 58 | 10 ± 3.6 | −0.1 ± 0.1 | 0.1 ± 0.4 |
| 0.5 | 350 ± 19c | 40 ± 24 | 2.5 ± 0.3 | −0.2 ± 0.1 |
| 1 | 275 ± 158 | 107 ± 56 | 7.5 ± 3.4 | 0.0 ± 0.4 |
| 2 | 20 ± 50 | 172 ± 88c | 27 ± 19 | 0.7 ± 0.5 |
| 4 | 11 ± 14 | 73 ± 50 | 47 ± 9.8c | 1.2 ± 0.2 |
| 8 | 1.9 ± 14 | 4.7 ± 27 | 28 ± 9.2 | 4.4 ± 0.9 |
| 16 | 9.4 ± 11 | 8.5 ± 8.3 | 24 ± 16 | 12 ± 1.4 |
| 32 | 6.5 ± 3.6 | 4.3 ± 2.7 | 10 ± 8.4 | 20 ± 24c |
aThe presented results are the average and standard deviation of three independent experiments. bThe standard doxycycline MIC values in parallel experiments were 0.5, 2.0, 8.0, and 32 μg/ml for the parental, #36, #36-4, and #36-4-18 isolates, respectively. cThe mMIC of the isolates is indicated in bold.