TABLE 1.
MICs of various β-lactams for P. mirabilis NO-113 and E. coli DH5α(pPm87), producing the TEM-87 enzymea
| Antibiotic(s) | MIC (μg/ml) for:
|
||
|---|---|---|---|
| P. mirabilis NO-113b | E. coli DH5α(pPm87)c | E. coli DH5αd | |
| Ampicillin | >64 | >64 | 4 |
| Amoxicillin-clavulanatee | 16 | 16 | 4 |
| Piperacillin | >256 | >256 | 1 |
| Piperacillin-tazobactamf | 8 | 0.5 | 0.5 |
| Cefazolin | >64 | 32 | 2 |
| Cefotaxime | 2 | 1 | ≤0.06 |
| Ceftazidime | 64 | >64 | 0.12 |
| Cefepime | 16 | 4 | ≤0.06 |
| Aztreonam | 32 | 64 | 0.12 |
a
The in vitro susceptibility of E. coli DH5α is also shown for comparison.
b
The enzymes detected in the crude extract of this strain by analytical IEF had pIs of 5.8, 7.1, and 8.7.
c
The enzyme detected in the crude extract of this strain by analytical IEF had a pI of 5.8.
d
No enzymes were detected in the crude extract of this strain.
e
Clavulanic acid was used at a 1:2 ratio.
f
Tazobactam was used at a fixed concentration of 4 μg/ml.