Authors: 
Huilan Zhang
Guangjin Hou
Manman Lu
Jinwoo Ahn
In-Ja L. Byeon
Christopher J. Langmead
Juan R. Perilla
Ivan Hung Peter
L. Gor’kov Zhehong
Gan William
W. Brey
David A. Case
Klaus Schulten
Angela M. Gronenborn
Tatyana Polenova
Journal: 
Journal of the American Chemical Society
Abstract: 
HIV-1 CA capsid protein possesses intrinsic conformational flexibility, which is essential for its assembly into conical capsids and interactions with host factors. CA is dynamic in the assembled capsid, and residues in functionally important regions of the protein undergo motions spanning many decades of timescales. Chemical shift anisotropy (CSA) tensors, recorded in magic-angle-spinning NMR experiments, provide direct residue-specific probes of motions on nano- to microsecond timescales. We combined NMR, MD, and Density-Functional-Theory calculations, to gain quantitative understanding of internal backbone dynamics in CA assemblies, and found that the dynamically averaged 15N CSA tensors calculated by this joined protocol are in remarkable agreement with experiment. Thus, quantitative atomic-level understanding of the relationships between CSA tensors, local backbone structure and motions in CA assemblies is achieved, demonstrating the power of integrating NMR experimental data and theory for characterizing atomic-resolution dynamics in biological systems.
Date: 
2016
Number: 
138
Pages: 
14066–14075
keywords: 
Virology
Biophysics
Physics
Structural Biology