Table 2.
Thermodynamic parameters for IcaR–dsDNA, antibiotics–dsDNA and antibiotics–IcaR interactions
| Samples | Binding constants KB (M−1) | ΔH (kcal/mol) | ΔS (cal/mol K) | Relative binding affinity (%) |
|---|---|---|---|---|
| Wild-type and mutated IcaR with 28E dsDNA | ||||
| Wild type | 2.0 ± 0.8 × 108 | 13.8 ± 0.2 | 84.3 | 100 |
| L23T | 1.3 ± 0.4 × 108 | 10.7 ± 0.2 | 72.9 | 65 |
| L23V | 1.5 ± 1.3 × 109 | 14.7 ± 0.2 | 91.2 | 750 |
| K33S | 4.1 ± 0.7 × 107 | 23.5 ± 0.3 | 114.0 | 21 |
| K33E | No binding | |||
| A35G | 3.9 ± 1.2 × 108 | 11.2 ± 0.1 | 76.8 | 195 |
| A35P | 1.0 ± 0.7 × 109 | 15.6 ± 0.2 | 93.5 | 500 |
| Wild-type IcaR with T2U 28E dsDNA | ||||
| T2U_DNA | 1.4 ± 0.3 × 107 | 15.1 ± 0.4 | 83.4 | 7 |
| Antibiotics with wild-type IcaR | Stoichiometry | |||
| Gentamicin | 2.6 ± 1.5 × 104 | −1.3 ± 0.5 | 15.7 | 0.59 ± 0.18 |
| Streptomycin | 8.0 ± 4.1 × 104 | −1.1 ± 0.1 | 18.8 | 0.88 ± 0.08 |
| Kanamycin | Not detectable | |||
| Antibiotics with 28E dsDNA | ||||
| Gentamicin | 8.6 ± 0.9 × 104 | 2.3 ± 0.1 | 30.2 | |
| Streptomycin | Difficult to calculate | |||
| Kanamycin | 1.1 ± 0.2 × 105 | 1.3 ± 0.1 | 27.5 | |