Table 1. Equilibrium dissociation constants of CREB–CRE and CREB–AP-1 complexes at 25°C determined by electrophoretic mobility shift analysis.
| Peptide |
ΔGCRE24 (kcal·mol–1) |
ΔGAP-123 (kcal·mol–1) |
ΔΔGCRE (ΔGmut – ΔGB70) (kcal·mol–1) |
ΔΔGAP-1 (ΔGmut – ΔGB70) (kcal·mol–1) |
ΔΔGspec (kcal·mol–1) |
| B70 | –21.5 ± 0.1 | –19.0 ± 0.2 | –2.5 ± 0.2 | ||
| Q6A | –24.0 ± 0.2 | –21.9 ± 0.1 | –2.5 | –2.9 | –2.1 ± 0.3 |
| E9A | –25.0 ± 0.2 | –21.9 ± 0.3 | –3.5 | –2.9 | –3.1 ± 0.1 |
| E10A | –22.4 ± 0.2 | –20.5 ± 0.3 | –0.9 | –1.5 | –1.9 ± 0.1 |
| R13A | –23.8 ± 0.5 | –20.7 ± 0.1 | –2.3 | –1.7 | –3.1 ± 0.5 |
| K14A | –24.6 ± 0.4 | –21.1 ± 0.3 | –3.1 | –2.1 | –3.5 ± 0.6 |
| R15A | –24.7 ± 0.4 | –21.5 ± 0.1 | –3.2 | –2.5 | –3.2 ± 0.3 |
| E16A | –23.4 ± 0.1 | –20.8 ± 0.1 | –1.9 | –1.8 | –2.6 ± 0.1 |
| V17A | –23.6 ± 0.1 | –19.8 ± 0.2 | –2.1 | –0.8 | –3.8 ± 0.3 |
| R18A | –24.3 ± 0.3 | –20.8 ± 0.3 | –2.8 | –1.8 | –3.5 ± 0.1 |
| L19A | –25.2 ±0.1 | –22.4 ± 0.4 | –3.7 | –3.4 | –2.8 ± 0.2 |
| M20A | –23.7 ± 0.2 | –21.6 ± 0.2 | –2.2 | –2.6 | –2.1 ± 0.2 |
| K21A | –25.1 ± 0.6 | –20.1 ± 0.2 | –3.6 | –1.1 | –5.0 ± 0.5 |
| R23A | –26.3 ± 0.4 | –21.5 ± 0.1 | –4.8 | –2.5 | –4.8 ± 0.3 |
| E24A | –24.2 ± 0.1 | –22.9 ± 0.1 | –2.7 | –3.9 | –1.3 ± 0.1 |
| R27A | –23.6 ± 0.3 | –20.4 ± 0.1 | –2.1 | –1.4 | –3.2 ± 0.3 |
| E28A | –23.5 ± 0.2 | –22.0 ± 0.2 | –2.0 | –3.0 | –1.5 ± 0.1 |
| R31A | –21.4 ± 0.1 | –18.3 ± 0.2 | +0.1 | +0.7 | –3.1 ± 0.2 |
| K32A | –20.8 ± 0.3 | –18.0 ± 0.2 | +0.7 | +1.0 | –2.8 ± 0.5 |
| K33A | –21.6 ± 0.1 | –18.1 ± 0.1 | –0.1 | +0.9 | –3.5 ± 0.1 |
| K34A | –23.4 ± 0.2 | –19.9 ± 0.6 | –1.9 | –0.9 | –3.5 ± 0.4 |
| E35A | –20.5 ± 0.1 | –19.0 ± 0.1 | +1.0 | 0 | –1.5 ± 0.05 |
| V37A | –22.0 ± 0.3 | –19.3 ± 0.3 | –0.5 | –0.3 | –2.7 ± 0.3 |
| C39A | –25.1 ± 0.1 | –23.0 ± 0.03 | –3.6 | –4.0 | –2.1 ± 0.1 |
| E41A | –22.5 ± 0.1 | –21.2 ± 0.2 | –1.0 | –2.2 | –1.3 ± 0.1 |
| N42A | –23.3 ± 0.2 | –20.8 ± 0.3 | –1.8 | –1.8 | –2.5 ± 0.1 |
| E48A | –24.2 ± 0.3 | –22.5 ± 0.3 | –2.7 | –3.5 | –1.7± 0.3 |
All values represent the average ± SE of at least three independent determinations. Values of ΔG were calculated from the equation ΔG = –RTlnKapp–1, where Kapp is the equilibrium dissociation constant, R = 1.987 × 103 kcal·mol–1·K–1 and T is the temperature in Kelvin.