Water-Proton-Spin-Lattice-Relaxation Dispersion of Paramagnetic Protein Solutions
 

Water-Proton-Spin-Lattice-Relaxation Dispersion of Paramagnetic Protein Solutions


Publication year: 2010
Source: Journal of Magnetic Resonance, In Press, Accepted Manuscript, Available online 10 November 2010</br>
Galina, Diakova , Yanina, Goddard , Jean-Pierre, Korb , Robert G., Bryant</br>
The paramagnetic contributions to water proton spin-lattice relaxation rate constants in protein systems spin-labeled with nitroxide radicals were re-examined. As noted by others, the strength of the dipolar coupling between water protons and the protein-bound nitroxide radical often appears to be larger than physically reasonable when the relaxation is assumed to be controlled by 3-dimensional diffusive processes in the vicinity of the spin label. We examine the effects of the surface in biasing the diffusive exploration of the radical region and derive a relaxation model that incorporates 2-dimensional dynamics at the interfacial layer. However, we find that the local 2-dimensional...</br>

Source: Journal of Magnetic Resonance