Table 4.
Thermodynamic profiles of poly(dA) . 2poly(dT) and 5v-dA12-x-dT12-x-dT12-3′ interaction with aminoglycosides in10 mM sodium cacodylate, 0.5 mM EDTA, pH 6.8 (unless indicated otherwise) and various KCl concentrations. T= 10 °C.
| Drug | [KCl] (mM) | ΔHHS (kcal/mol base triplet) |
Tm0 (°C ) | Tm (°C ) | ΔCp (cal/mol K) | Kobs(10°C)(M −1) |
|---|---|---|---|---|---|---|
| poly(dA) 2poly(dT) | ||||||
| Neomycin | 100 | 1.20 | 22.7 | 54.2 | −218 ±15 | NA |
| Neomycin | 150 | 1.59 | 33.9 | 46.5 | −116 ± 34 | NA |
| Neomycin | 200 | 2.00 | 41.0 | 43.9 | − 76 ± 13 | NA |
| Neomycin | 100 (pH 5.5)a | 1.16 | 22.4 | 28.6 | −98 ±13 | (6.2 ± 0.5) × 105 |
| Neomycin | 120 (pH 5.5)a | 1.50 | 27.5 | 32.4 | −90 ±18 | (4.0 ±0.1) × 105 |
| Neomycin | 140 (pH 5.5)a | 1.70 | 31.4 | 34.4 | −87 ± 4 | (2.4 ±0.1) × 105 |
| Paromomycin | 100 | 1.20 | 22.7 | 32.2 | −83 ± 15 | NA |
| Paromomycin | 150 | 1.59 | 33.9 | 36.3 | −29 ±9 | NA |
| Paromomycin | 200 | 2.00 | 41.0 | 42.5 | −23 ±11 | NA |
| Ribostamycin | 100 | 1.20 | 22.7 | 26.2 | −30 ±8 | NA |
| 5′-dA12-x-dT12-x-dT12-3′ | ||||||
| Neomycin | 100 | 1.33 | 30.0 | 36.5 | −310 ± 43 | (1.4 ± 0.2) × 106 |
| Neomycin | 150 | 1.59 | 34.8 | 37.0 | −158 ± 30 | (2.5 ± 0.3) × 105 |
| Neomycin | 200 | 1.78 | 37.3 | 38.7 | −84 ±12 | (1.4 ± 0.1) × 105 |
| Neomycin | 250 | 1.81 | 42.4 | 43.7 | − 17 ± 22 | (9.3 ± 0.1) × 104 |
a
Experiments were done at pH 5.5.