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Updated: Mar 7, 2026

Author Spotlight: Exploring Intrinsically Disordered Protein Dynamics Through NMR Relaxation Experiments
Published on: November 1, 2024
Metabasin transitions are Johari-Goldstein relaxation events
Marcus T Cicerone1, Madhusudan Tyagi1
1National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8543, USA.
Abstract:
We show that by representing quasi-elastic and inelastic neutron scattering from propylene carbonate (PC) with an explicitly heterogeneous model, we recover signatures of two distinct localized modes in addition to diffusive motion. The intermediate scattering function provides access to the time-dependence of these two localized dynamic processes, and they appear to correspond to transitions between inherent states and between metabasins on a potential energy landscape. By fitting the full q-dependence of inelastic scattering, we confirm that the Johari-Goldstein (βJG) relaxation in PC is indistinguishable from metabasin transitions.
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