Table 1.
Comparison of the minimum inhibitory concentration of ampicillin for growth of E. coli TP112 and TP132 strains containing plasmids encoding BLIP alanine-scanning mutants versus the Ki value for inhibition of TEM-1 β-lactamase by the purified BLIP derivatives. “No BLIP” refers to the E. coli strain containing the pTP123 plasmid that does not encode BLIP. “Wt BLIP” refers to the E. coli strain containing the pGR32 plasmid that encodes BLIP. The Ki data is from Zhang and Palzkill28 and the ΔΔG values are calculated from the Ki values (Materials and Methods).
| Ampicillin MIC (μg/ml) | ||||
|---|---|---|---|---|
| BLIP mutant | E. coli TP112 | E. coli TP132 | Ki (nM) | ΔΔG (kJ/mol) |
| No BLIP | 256 | >256 | - | - |
| Wt BLIP | 1.5 | 4 | 0.5 | - |
| E31A | 8 | 12 | 2.0 | 3.4 |
| S35A | 1.5 | 4 | 0.5 | 0 |
| F36A | 24 | 24 | 40 | 10.8 |
| S39A | 1.5 | 4 | 0.3 | −1.3 |
| H41A | 64 | 64 | 34 | 10.4 |
| G48A | 2 | 12 | 0.7 | 0.8 |
| D49A | 3 | 16 | 20 | 9.1 |
| Y50A | 1 | 4 | 0.01 | −9.7 |
| Y51A | 1.5 | 4 | 0.5 | 0 |
| Y53A | 4 | 24 | 21 | 9.3 |
| S71A | 3 | 6 | 0.2 | −2.3 |
| E73A | 1.5 | 6 | 0.4 | −0.5 |
| K74A | 3 | 24 | 46 | 11.2 |
| W112A | 1.5 | 16 | 13 | 8.0 |
| S113A | 1 | 4 | 0.1 | −4.0 |
| G141A | 3 | 8 | 1.8 | 3.18 |
| F142A | 2 | 16 | 16 | 8.58 |
| Y143A | 1 | 4 | 0.6 | 0.5 |
| R144A | 1 | 6 | 0.6 | 0.5 |
| H148A | 24 | 32 | 21 | 9.3 |
| W150A | 96 | 256 | 184 | 14.6 |
| R160A | 2 | 24 | 11 | 7.7 |