Table 1.
Summary of the thermodynamic properties of S100B binding to p53, TRTK12, NDR, HDM2 and HDM4 and determined using ITC experiments as well as the comparison with structure-based calculations.
| Peptide | Kd μM | ΔCp, exp kJ·mol-1 K-1 | ΔCp, calc kJ·mol-1 K-1 |
|---|---|---|---|
| TRTK12 | 2 ± 1 | -1.3 ± 0.2 | -1.1 ± 0.1 |
| p53, low salt | 2 ± 1 | -1.0 ± 0.1 | -1.0 ± 0.1 |
| p53, high salt | 20 ± 5 | -1.2 ± 0.3 | -1.0 ± 0.1 |
| NDR | 2 ± 1, 0.4 ± 0.2a | -1.5 ± 0.3 | -1.9 ± 0.2 |
| HDM2 | 0.5 ± 0.2 | -1.3 ± 0.2 | -1.0 ± 0.1b |
| HDM4 | 0.07 ± 0.03 | -1.7 ± 0.2 | -0.7 ± 0.1b |
a
The interaction between S100B and NDR was fit to a sequential binding model, where each S100B monomer had a unique binding affinity.
b
These values were calculated using homology models of the S100B dimer (PDB id: 1DT7) binding to two peptides.