TABLE 2.
Kinetic parameters of certain OXA-48-like β-lactamasesa
| Antibiotic and parameter | Value for indicated β-lactamase |
||||||||
|---|---|---|---|---|---|---|---|---|---|
| OXA-48 | OXA-162 | OXA-163 | OXA-181 | OXA-204 | OXA-232 | OXA-245 | OXA-436 | OXA-519 | |
| Benzylpenicillin | |||||||||
| kcat (s−1) | 245 | 123 | 23 | 444 | 353 | 125 | NE | 900 | NE |
| Km (μM) | 40 | 35 | 13 | 90 | 90 | 60 | NE | 200 | NE |
| kcat/Km (mM−1/s−1) | 6,100 | 3,400 | 1,800 | 5,000 | 4,100 | 2,100 | NE | 4,500 | NE |
| Ampicillin | |||||||||
| kcat (s−1) | 955 | 269 | 23 | 218 | 389 | 132 | 1,200 | 600 | 131 |
| Km (μM) | 400 | 315 | 315 | 170 | 450 | 220 | 35 | 5 | 776 |
| kcat/Km (mM−1/s−1) | 2,400 | 830 | 70 | 1,300 | 860 | 600 | 3,428 | 120,000 | 169 |
| Oxacillin | |||||||||
| kcat (s−1) | 130 | 3 | 34 | 90 | 56 | 156 | NE | NE | 8 |
| Km (μM) | 95 | 75 | 90 | 80 | 100 | 130 | NE | NE | 338 |
| kcat/Km (mM−1/s−1) | 1,400 | 40 | 370 | 1,100 | 540 | 1,200 | NE | NE | 23 |
| Piperacillin | |||||||||
| kcat (s−1) | 75 | NE | 8 | NE | NE | 380 | NE | NE | 36 |
| Km (μM) | 410 | NE | 70 | NE | NE | 540 | NE | NE | 109 |
| kcat/Km (mM−1/s−1) | 180 | NE | 110 | NE | NE | 700 | NE | NE | 330 |
| Temocillin | |||||||||
| kcat (s−1) | 0.3 | 0.7 | NH | 0.3 | 0.5 | 0.03 | NE | 3 | >12 |
| Km (μM) | 45 | 170 | NH | 60 | 75 | 60 | NE | 200 | >1,000 |
| kcat/Km (mM−1/s−1) | 6 | 4 | ND | 5 | 7 | 0.5 | NE | 15 | 8.8 |
| Imipenem | |||||||||
| kcat (s−1) | 5 | 11 | 0.03 | 7.5 | 4 | 0.2 | 4.4 | 6 | 2.1 |
| Km (μM) | 13 | 25 | 530 | 13 | 9 | 9 | 11 | 20 | 982 |
| kcat/Km (mM−1/s−1) | 370 | 420 | 0.06 | 550 | 420 | 20 | 400 | 300 | 2.138 |
| Meropenem | |||||||||
| kcat (s−1) | 0.07 | 0.1 | >0.1 | 0.1 | 0.05 | 0.03 | 0.11 | 0.14 | 3.4 |
| Km (μM) | 10 | 80 | >2,000 | 70 | 60 | 100 | 2 | 3 | 358 |
| kcat/Km (mM−1/s−1) | 6 | 1.3 | 0.03 | 1.5 | 0.8 | 0.3 | 55 | 4,666 | 9.497 |
| Ertapenem | |||||||||
| kcat (s−1) | 0.13 | 0.3 | 0.05 | 0.2 | 0.1 | 0.04 | 0.29 | 0.4 | 1.1 |
| Km (μM) | 100 | 30 | 130 | 100 | 90 | 110 | 80 | 160 | 83 |
| kcat/Km (mM−1/s−1) | 1 | 9 | 0.3 | 2 | 1 | 0.4 | 3,625 | 2.5 | 13.25 |
| Cefotaxime | |||||||||
| kcat (s−1) | >9 | 3 | 10 | >62 | 12 | >6.5 | NE | 6 | >1.3 |
| Km (μM) | >900 | 310 | 45 | >1,000 | 990 | >1,000 | NE | 130 | >1,000 |
| kcat/Km (mM−1/s−1) | 10 | 10 | 230 | 13 | 12 | 6 | NE | 46.15 | 0.39 |
| Ceftazidime | |||||||||
| kcat (s−1) | NH | ND | 8 | ND | ND | >0.6 | 0.3 | 7 | 0.02 |
| Km (μM) | NH | NH | >1,000 | NH | NH | >1,000 | 110 | 150 | 373 |
| kcat/Km (mM−1/s−1) | NH | ND | 3 | ND | ND | 0.1 | 2,727 | 4,666 | 0.05 |
| Cefepime | |||||||||
| kcat (s−1) | 1 | NE | 2 | NE | NE | 13 | NE | NE | >1.3 |
| Km (μM) | 160 | NE | 350 | NE | NE | 1,200 | NE | NE | >1,000 |
| kcat/Km (mM−1/s−1) | 6 | NE | 6 | NE | NE | 10 | NE | NE | 0.31 |
| Cephalothin | |||||||||
| kcat (s−1) | 44 | 12 | 3 | 13 | 12 | 13 | NE | NE | >13 |
| Km (μM) | 195 | 180 | 10 | 250 | 270 | 125 | NE | NE | >1,000 |
| kcat/Km (mM−1/s−1) | 255 | 70 | 300 | 50 | 45 | 105 | NE | NE | 3.5 |
Kinetic parameter values for OXA-48 are from reference 44, except those for benzylpenicillin, piperacillin, and cefepime, which are from reference 22. Values for OXA-163 are from reference 44, except those for piperacillin and cefepime, which are from reference 32. Values for OXA-232 are from reference 44, except those for piperacillin and cefepime, which are from reference 26. All values for OXA-162, OXA-181, and OXA-204 are from reference 44. All values for OXA-245 are from reference 307. All values for OXA-436 are from reference 214. All values for OXA-519 are from reference 31. kcat, number of times each enzyme site converts substrate to product per unit time; Km, inverse measure of affinity; NE, not evaluated; ND, not determined; NH, not detectable.