Table 1. Rate Constants of Loop Closure in p53-TAD(1–93) and Influence of MDM2(2–125) Binding and Phosphorylationa.
| k1 (×106 s–1) | k2 (×105 s–1) | k3 (×104 s–1) | |
|---|---|---|---|
| Oxa13-W23 | 2.81 ± 0.46 | -- | |
| Oxa13-W23 + MDM2 | 0.30 ± 0.12 | ||
| Oxa13-W23-phos | 2.27 ± 0.40 | 1.3 ± 0.7 | |
| Oxa13-W23-phos + MDM2 | -- | 4 ± 2 | |
| W23-Oxa31 | 3.24 ± 0.83 | 3.9 ± 1.7 | |
| W23-Oxa31 + MDM2 | 0.64 ± 0.50 | 4.5 ± 0.8 | |
| W23-Oxa31-phos | 1.9 ± 0.6 | 3.1 ± 1.5 | |
| W23-Oxa31-phos + MDM2 | n.d. | n.d. | n.d. |
| Oxa31-W53 | 1.39 ± 0.47 | 7.5 ± 4.9 | |
| Oxa31-W53 + MDM2 | 2.1 ± 1.1 | 2.2 ± 0.5 | 0.58 ± 0.25 |
| Oxa31-W53-phos | 2.6 ± 0.9 | ||
| Oxa31-W53-phos + MDM2 | 1.01 ± 0.24 | 0.43 ± 0.12 | 0.11 ± 0.06 |
| W53-Oxa60 | 3.59 ± 0.52 | 2.8 ± 2.7 | |
| W53-Oxa60 + MDM2 | 4.20 ± 0.72 | 2.8 ± 0.9 | 1.13 ± 0.30 |
| W53-Oxa60-phos | 3.33 ± 0.73 | 1.7 ± 1.5 | |
| W53-Oxa60-phos + MDM2 | 10 ± 5 | 1.1 ± 0.4 | 0.53 ± 0.27 |
a
“--“: Experimental error larger than value. n.d.: Not determined because of protein aggregation. Errors are standard errors from data fits.