Figure 3. Transition state ensembles for c-Myb-KIX binding.

The TS ensembles were obtained by using Φ-values as structural restraints in molecular dynamics simulations. The KIX domain is represented in red, whereas c-Myb is represented in blue. A contact map, highlighting the intra-molecular and inter-molecular contacts in each transition state, is reported in the middle (with a red and blue square identifying the KIX and c-Myb structures, respectively). Residue T11, which is critical in the I72V mutant but does not make any key contacts in wild type KIX, is highlighted in yellow both in the structures and in the contact maps. The structural ensemble of c-Myb in the transition state, together with its average structure (reported in blue), is shown below the relevant contact map.