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Updated: Apr 25, 2026

Author Spotlight: Exploring Intrinsically Disordered Protein Dynamics Through NMR Relaxation Experiments
Published on: November 1, 2024
Local isotropic diffusion approximation for coupled internal and overall molecular motions in NMR spin relaxation
Michelle L Gill1, Arthur G Palmer
1Department of Biochemistry and Molecular Biophysics, Columbia University , 630 West 168th Street, New York, New York 10032, United States.
Abstract:
The present work demonstrates that NMR spin relaxation rate constants for molecules interconverting between states with different diffusion tensors can be modeled theoretically by combining orientational correlation functions for exchanging spherical molecules with locally isotropic approximations for the diffusion anisotropic tensors. The resulting expressions are validated by comparison with correlation functions obtained by Monte Carlo simulations and are accurate for moderate degrees of diffusion anisotropy typically encountered in investigations of globular proteins. The results are complementary to an elegant, but more complex, formalism that is accurate for all degrees of diffusion anisotropy [Ryabov, Y.; Clore, G. M.; Schwieters, C. D. J. Chem. Phys. 2012, 136, 034108].
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