TABLE 3.
MICs and basal and induced levels of ampC and creD expression in the studied strains
| Strain | MIC (μg/ml) |
Relative mRNA levela |
||||||||
|---|---|---|---|---|---|---|---|---|---|---|
|
ampC |
creD (blrD) |
|||||||||
| CAZ | FEP | IMP | MER | PTZ | ATM | Basal | Inducedb | Basal | Induced | |
| PAO1 | 1.5 | 1.5 | 2 | 0.38 | 2 | 4 | 1 | 78 ± 34 | 1 | 24 ± 9.1 |
| PA ΔnZ | 1 | 1.5 | 1 | 0.38 | 2 | 4 | −2.1 ± 1.5 | 469 ± 230 | 1.1 ± 0.3 | 54 ± 18 |
| PAΔD | 8 | 4 | 2 | 1 | 32 | 12 | 47 ± 9.5 | 134 ± 11 | 1.1 ± 0.3 | 2.7 ± 0.7 |
| PAΔDnZ | 2 | 1.5 | 1 | 0.5 | 3 | 4 | 1.0 ± 0.4 | 483 ± 26 | 2.8 ± 1.6 | 99 ± 15 |
| PAΔdB | 24 | 12 | 2 | 0.5 | 64 | 24 | 51 ± 16 | 232 ± 67 | 83 ± 7 | 120 ± 29 |
| PAΔdBnZ | 1.5 | 2 | 1 | 0.38 | 3 | 4 | 3.0 ± 1.9 | 661 ± 374 | 4.0 ± 0.8 | 95 ± 45 |
| PAdacBΔD | 96 | 48 | 2 | 1.5 | >256 | 64 | 1,770 ± 414 | 1,950 ± 480 | 51 ± 24 | 81 ± 40 |
| PAdacBΔDnZ | 4 | 3 | 1 | 0.5 | 16 | 8 | 40 ± 17 | 906 ± 80 | 1.9 ± 1.3 | 418 ± 170 |
| PAΔDDh2Dh3 | 32 | 16 | 2 | 1 | >256 | 32 | 1,020 ± 87 | 1,105 ± 88 | 1.3 ± 0.3 | 1.6 ± 0.7 |
| PAΔDDh2Dh3nZ | 3 | 3 | 1.5 | 1 | 8 | 8 | 57 ± 31 | 905 ± 407 | −1.4 ± 0.1 | 1.0 ± 0.3 |
| PAΔR | 2 | 2 | 0.5 | 0.25 | 4 | 4 | 3.8 ± 0.4 | 3.3 ± 0.8 | 1.6 ± 0.1 | 189 ± 8 |
| PAΔC | 1 | 1 | 0.5 | 0.25 | 2 | 2 | NA | NA | ND | ND |
a
Relative amount of ampC or creD (blrD) mRNA compared to the basal levels ± standard deviation in strain PAO1. NA, not applicable; ND, not determined.
b
Induction experiments were carried out with 50 μg/ml of cefoxitin.