Figure 4. Comparison with experimental conformational changes.

Cumulative overlaps CO(m) between ANM modes and the experimentally observed deformation between the open and closed forms of NAGK are plotted for subsets of m modes, in the range 1≤m≤50 (see equation (7) in Methods ). We note that the first 3 ANM modes (among 3N-6 = 1542 modes) accessible to the open form (red) yield an overlap of 0.75 with the experimentally observed reconfiguration from open to closed state of the enzyme. In the case of the closed form, the first 3 modes yield an overlap of 0.61. In either case, a small subset of modes intrinsically accessible to the structure attain a cumulative overlap of >0.80, pointing to the pre-disposition of the structure to undergo its functional changes in conformation between the open and closed forms.