Separability between overall and internal motion: A protein folding problem

The separability between overall and internal motions is evaluated over multiple folding trajectories of the villin headpiece subdomain. The analysis, which relies on the Prompers‐Brüschweiler separability index, offers a potentially useful perspective on protein folding. The protein is considered folded in this study, not when it reaches some static target, but rather when it tumbles as a dynamically constrained object. The analysis also demonstrates how the separability index, when applied to protein folding simulations, can facilitate the analysis of NMR relaxation data. Proteins 2012;. © 2012 Wiley Periodicals, Inc.