D4 opens wider in Apo-deP than in Apo-P in MD simulations. (A, C, and E) Angle (θ) between the centers of mass (spheres in A) of D1–D3 and D4. (B, D, and F) Distances between the center of mass of D4 and the metal site (spheres in B). (C) The instantaneous angle between the centers is plotted. (D) Plot showing the instantaneous separation between the centers of mass in panel D. (E) Histogram marking the frequency with which the angle occurs over the equilibrated portions of the MD trajectories from 5 to 120 ns. (F) Histogram plotting the frequency with which the separation occurs between 5 and 120 ns. Green represents the Apo-P simulation and purple represents Apo-deP. To see this figure in color, go online.