Discrete Three-dimensional Representation of Macromolecular Motion from eNOE-based Ensemble Calculation

Abstract

Three-dimensional structural data and description of dynamics are fundamental to infer and understand protein function. Structure determination by NMR follows well-established protocols while NMR relaxation phenomena provide insights into local molecular dynamics. However, methods to detect concerted motion were not pursued until very recently. Here, we present an ensemble-based structure determination protocol using ensemble-averaged distance restraints obtained from exact NOE (eNOE) rate constants. An application of our protocol to the model protein GB3 established an ensemble of structures that reveals correlated motion across the ?-sheet and concerted motion between the backbone and side chains localized in the core. Furthermore, the data repudiate concerted conformational exchange between the ?-sheet and the ?-helix.