Journal of Magnetic Resonance
This work examines the robustness of fitting of parameters describing conformational exchange (kex, pa/b, and Δω) processes from CPMG relaxation dispersion data. We have analyzed the equations describing conformational exchange processes for the intrinsic inter-dependence of their parameters that leads to the existence of multiple equivalent solutions, which equally satisfy the experimental data. We have used Monte-Carlo simulations and fitting to the synthetic data sets as well as the direct 3-D mapping of the parameter space of kex, pa/b, and Δω to quantitatively assess the degree of the parameter inter-dependence. The demonstrated high correlation between parameters can preclude accurate dynamics parameter estimation from NMR spin-relaxation data obtained at a single static magnetic field. The strong parameter inter-dependence can readily be overcome through acquisition of spin-relaxation data at more than one static magnetic field thereby allowing accurate assessment of conformational exchange properties.
Kovriguine, Evgueni; Kempf, James G.; Grey, Michael J.; and Loria, J. Patrick, "Faithful Estimation of Dynamics Parameters from CPMG Relaxation Dispersion Measurements" (2006). Chemistry Faculty Research and Publications. 232.
ADA accessible version
Accepted version. Journal of Magnetic Resonance, Vol. 180, No. 1 (May 2006): 93-104. DOI: © 2006 Elsevier Inc. Used with permission.