TABLE 2.
Binding affinities of β-lactams for S. aureus PBPs
| PBP | Strain | IC50 (μg/ml)a |
|||
|---|---|---|---|---|---|
| Ceftaroline | Cefotaxime | Ceftriaxone | Penicillin G | ||
| PBP1 | ATCC 29213 | 0.5 | 0.5 | 0.25 | 4 |
| 873 | 8 | 4 | 2 | 0.5 | |
| 510 | 0.5 | 2 | 0.5 | 128 | |
| 2149A | 1 | 0.5 | 4 | 2 | |
| 1287 | 0.125 | 4 | 1 | 4 | |
| 25 | 0.5 | 1 | 16 | 0.5 | |
| PBP2 | ATCC 29213 | 0.25 | 1 | 0.25 | 8 |
| 873 | 0.5 | 0.5 | 0.5 | 0.5 | |
| 510 | 0.125 | 0.5 | 0.25 | 64 | |
| 2149A | 1 | 2 | 1 | >128 | |
| 1287 | 4 | 1 | 1 | 4 | |
| 25 | 0.25 | 0.5 | 2 | 1 | |
| PBP2a | ATCC 29213 | NP | NP | NP | NP |
| 873 | 0.5 | >128 | >128 | 64 | |
| 510 | 0.25 | >128 | 1 | 64 | |
| 2149A | 1 | >128 | >128 | 2 | |
| 1287 | 1 | 4 | 2 | 4 | |
| 25 | 0.01 | 0.5 | 0.25 | 4 | |
| PBP3 | ATCC 29213 | 0.125 | 1 | 1 | 1 |
| 873 | 0.125 | 0.125 | 0.25 | 0.03 | |
| 510 | 0.125 | 0.25 | 0.25 | 4 | |
| 2149A | 0.5 | 4 | 2 | 2 | |
| 1287 | 0.1 | 1 | 1 | 0.25 | |
| 25 | 0.25 | 0.25 | 1 | 0.5 | |
| PBP4 | ATCC 29213 | >8 | >8 | >8 | >8 |
| 873 | >128 | >128 | >128 | >128 | |
| 510 | >128 | >128 | >128 | 64 | |
| 2149A | >128 | >128 | >128 | >128 | |
| 1287 | 64 | >128 | >128 | 4 | |
| 25 | ND | ND | ND | ND | |
a
NP, ATCC 29213, as a MSSA strain, lacks PBP2a. ND, no demonstrable binding of Bocillin FL to PBP4 was observed (17).