Table 3. Relative MIC fold change of resistant transformants obtained from the FtsI-based libraries and the DacC-based library against five different β-lactam antibiotics.
| Strain No. | Mutant PBPs | Amino acid substitutions | Antibiotics* | ||||
| PG | AMP | CE | XM | CT | |||
| DA16010 | DacC | Wild type | 1.0 | 1.0 | 1.0 | 1.0 | 1.0 |
| DA19904 | DacC | M369L, W384C | 2.2 | 2.0 | 2.3 | 2.3 | 2.5 |
| DA19906 | DacC | S6Y, P199S, Q365H, L368F | 2.0 | 1.5 | 2.3 | 2.3 | 2.0 |
| DA19908 | DacC | F21L, S120T | 2.3 | 1.5 | 2.0 | 2.3 | 2.0 |
| DA19909 | DacC | M45I, A104T, S147N | 2.7 | 2.0 | 2.3 | 2.8 | 2.0 |
| DA19911 | DacC | T92M, G325W | 2.2 | 2.0 | 3.0 | 2.8 | 2.0 |
| DA19912 | DacC | G146R, M371I | 3.5 | 1.5 | 3.0 | 2.3 | 2.5 |
| DA16020 | FtsI | Wild type | 1.0 | 1.0 | 1.0 | 1.0 | 1.0 |
| DA17021 | FtsI | P311S | 2.4 | 1.5 | 4.0 | 3.7 | 1.3 |
| DA17023 | FtsI | V545I | 2.6 | 1.5 | 1.3 | 2.3 | 0.7 |
| DA17025 | FtsI | V377I | 1.6 | 1.0 | 1.7 | 1.7 | 1.3 |
| DA20073 | FtsI | V545I, N579K | 4.4 | 3.5 | 5.3 | 3.7 | 1.7 |
| DA20075 | FtsI | V545I, P50S | 4.8 | 4.0 | 4.7 | 6.0 | 1.3 |
| DA20078 | FtsI | P311S, A49V, I159V | 2.8 | 2.0 | 3.0 | 4.0 | 1.3 |
*MIC values were determined under 2 mM arabinose induction.
Abbreviations for antibiotics: PG, penicillin G; AMP, ampicillin; CE, cephalothin; XM, cefuroxime; CT, cefotaxime.