TABLE 4.
Kinetic values of recombinantly expressed and purified OXA-48, OXA-48:P68A, and OXA-48:P68A,Y211Sa
| Substrateb | OXA-48 |
OXA-48:P68A |
OXA-48:P68A,Y211S |
||||||
|---|---|---|---|---|---|---|---|---|---|
| Km (µM) | kcat (s−1) |
kcat/Km
(s−1 mM−1) |
Km (µM) | kcat (s−1) |
kcat/Km
(s−1 mM−1) |
Km (µM) | kcat (s−1) |
kcat/Km
(s−1 mM−1) |
|
| AMP | 370 ± 70 | 608 ± 53 | 1,643 ± 455 | 77 ± 12 | 25 ± 1 | 331 ± 66 | 211 ± 26 | 18 ± 1 | 86 ± 14 |
| PIP | 898 ± 155 | 3.9 ± 0.5 | 4 ± 1 | 290 ± 67 | 0.15 ± 0.02 | 0.5 ± 0.2 | 155 ± 38 | 0.06 ± 0.01 | 0.4 ± 0.2 |
| NIT | 226 ± 34 | 141 ± 12 | 624 ± 148 | 53 ± 8 | 37 ± 2 | 703 ± 149 | 63 ± 9 | 12 ± 1 | 193 ± 40 |
| CAZ | 300 ± 150 | 3.0 ± 0.8 | 10 ± 8 | 220 ± 50 | 26 ± 3 | 117 ± 41 | 190 ± 40 | 42 ± 5 | 220 ± 72 |
| FEP | 1,678 ± 686 | 1.7 ± 0.6 | 1.0 ± 0.8 | 462 ± 126 | 0.5 ± 0.1 | 1.2 ± 0.5 | 1,459 ± 635 | 1.1 ± 0.4 | 0.8 ± 0.6 |
| IMI | 13 ± 2 | 4.8 ± 0.2 | 365 ± 71 | 4.2 ± 0.9 | 0.80 ± 0.04 | 190 ± 50 | 14 ± 3 | 0.57 ± 0.04 | 41 ± 11 |
| MEM | 4 ± 1 | 0.71 ± 0.02 | 177 ± 50 | 3 ± 1 | (8 ± 0.8) × 10−4 | 0.3 ± 0.1 | 2 ± 1 | (2 ± 0.2) × 10−3 | 1.2 ± 0.7 |
a
Errors are displayed as 95% confidence intervals based on a minimum of triplicates.
b
AMP, ampicillin; PIP, piperacillin; NIT, nitrocefin; CAZ, ceftazidime; FEP, cefepime; IMI, imipenem; MEM, meropenem.