TABLE 2.
Kinetic parameters of beta-lactamase inactivation by QPX7728
| Enzyme | k2/K (M−1 s−1) | koff, s−1 | Residence time, min | Kd, nMa | Stoichiometry |
|---|---|---|---|---|---|
| KPC-2 | (3.6 ± 0.1) × 105 | (9.0 ± 1.4) × 10−5 | 189 ± 31 | 0.25 ± 0.03 | 1 |
| KPC-3 | (4.1 ± 1.0) × 105 | (1.26 ± 0.07) × 10−4 | 133 ± 8 | 0.31 ± 0.06 | 1 |
| BKC-1 | (1.82 ± 0.04) × 106 | (1.1 ± 0.1) × 10−4 | 154 ± 14 | 0.060 ± 0.005 | 1 |
| FRI-1 | (1.15 ± 0.03) × 106 | (1.2 ± 0.2) × 10−4 | 138 ± 24 | 0.11 ± 0.01 | 1 |
| SME-2 | (1.2 ± 0.1) × 106 | (1.8 ± 0.2) × 10−4 | 94 ± 11 | 0.15 ± 0.02 | 1 |
| CTX-M-15 | (6.9 ± 0.6) × 105 | (8.0 ± 1.0) × 10−5 | 220 ± 33 | 0.11 ± 0.02 | 1 |
| SHV-12 | (1.1 ± 0.2) × 105 | (3.0 ± 0.2) × 10−3 | 5.5 ± 0.3 | 28 ± 4 | 1 |
| TEM-43 | (1.9 ± 0.3) × 106 | (3.2 ± 0.2) × 10−4 | 53 ± 3 | 0.17 ± 0.02 | 1 |
| P99 | (6.3 ± 0.7) × 104 | (3.3 ± 0.3) × 10−5 | 506 ± 51 | 0.53 ± 0.06 | 1 |
| OXA-48 | (2.75 ± 0.09) × 106 | (3.6 ± 0.2) × 10−4 | 47 ± 3 | 0.13 ± 0.01 | 1 |
| OXA-23 | (9.9 ± 0.6) × 105 | (1.6 ± 0.2) × 10−3 | 11 ± 2 | 1.6 ± 0.2 | 2 |
| OXA-24 | (1.5 ± 0.2) × 106 | (9.0 ± 1.0) × 10−4 | 20 ± 3 | 0.58 ± 0.10 | 1 |
| OXA-58 | (1.07 ± 0.08) × 106 | (3.5 ± 0.3) × 10−4 | 4.8 ± 0.5 | 3.2 ± 0.3 | 1 |
| NDM-1 | NDb | ND | ND | 32 ± 14 | ND |
| VIM-1 | ND | ND | ND | 7.5 ± 2.1 | ND |
| IMP-1 | ND | ND | ND | 240 ± 30 | ND |
a
Kd values for serine beta-lactamases were derived from the ratio of koff and k2/K. Kd values for MBLs were based on Kis.
b
ND, not done.