Table 1.
Change in the EF-hand angles (θ in °) of CaM during the association with CaMKI along the binding route at different values of Z̄ (normalized intermolecular contacts between CaM and CaMBT). θ calculated for the unbound holoCaM (PDB ID: 1CLL) and the CaM from native bound complex (PDB ID: 2L7L) are also presented (see the Model and Methods section for the calculation of θ). EF-hand of CaM is defined as helix-loop-helix Ca2+-binding motif (helices A/B and C/D in nCaM constitute EF hand I and II, respectively; helices E/F and G/H in cCaM constitute EF hand III and IV, respectively; see Fig. 1(A) and (B)).
| Intermolecular contacts | EF I (θI) | EF II (θII) | EF III (θIII) | EF IV (θIV) |
|---|---|---|---|---|
| Unbound (holo) | 95.52 | 97.29 | 80.67 | 89.17 |
| Z̄~0.3 | 93.68 (±0.11) | 87.91 (±0.16) | 79.07 (±0.14) | 87.15 (±0.17) |
| Z̄~0.6 | 92.49 (±0.03) | 88.33 (±0.03) | 75.50 (±0.04) | 91.16 (±0.04) |
| Z̄~0.8 | 95.36 (±0.05) | 99.75 (±0.05) | 73.19 (±0.06) | 97.76 (±0.07) |
| Native complex | 92.81 | 81.78 | 84.02 | 85.09 |