TROSY effects in MAS solid-state NMR

Use of transverse relaxation-optimized spectroscopy (TROSY) type techniques had a dramatic impact on the study of large proteins with a molecular weight >30kDa for solution-state NMR. In the solid-state, such an effect would not be expected a prior, as the investigated molecules are immobilized. However, local motions induce fluctuations of the local fields experienced by the nuclear spins and, this way, are effective for relaxation. We demonstrate that protein dynamics can significantly influence the resonance line width in ultra high resolution MAS (magic angle spinning) solid-state NMR experiments. Averaging of the (NH alpha/beta)-N-15 multiplet components as a consequence of H-1 decoupling induces effective broadening of the N-15 resonance. Application of TROSY type techniques that select only the narrow component of the multiplet pattern results in an increased resolution and, thus, will be of benefit for MAS solid-state NMR spectroscopy. (C) 2008 Wiley Periodicals, Inc.