Local Isotropic Diffusion Approximation for Coupled Internal and Overall Molecular Motions in NMR Spin Relaxation
نویسندگان
چکیده
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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Correction to “Local Isotropic Diffusion Approximation for Coupled Internal and Overall Molecular Motions in NMR Spin Relaxation”
T original version of Figure 66 is incorrect; the corrected figure is shown below. In addition, the sentence “The experimental data arefit in the fast-exchange limit with a population of the B state of 0.68, yielding an average τm = 5.29 ns and S 2 = 0.13” (p 11126) should read “The experimental data are fit in the fastexchange limit with S = 1 (by construction, eq 21) and a population of the B...
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