Attenuated T 2 relaxation by mutual cancellation of dipole–dipole coupling and chemical shift anisotropy indicates an avenue to NMR structures of very large biological macromolecules in solution
- 11 November 1997
- journal article
- Published by Proceedings of the National Academy of Sciences in Proceedings of the National Academy of Sciences
- Vol. 94 (23), 12366-12371
- https://doi.org/10.1073/pnas.94.23.12366
Abstract
Fast transverse relaxation of 1H, 15N, and 13C by dipole-dipole coupling (DD) and chemical shift anisotropy (CSA) modulated by rotational molecular motions has a dominant impact on the size limit for biomacromolecular structures that can be studied by NMR spectroscopy in solution. Transverse relaxation-optimized spectroscopy (TROSY) is an approach for suppression of transverse relaxation in multidimensional NMR experiments, which is based on constructive use of interference between DD coupling and CSA. For example, a TROSY-type two-dimensional 1H,15N-correlation experiment with a uniformly 15N-labeled protein in a DNA complex of molecular mass 17 kDa at a 1H frequency of 750 MHz showed that 15N relaxation during 15N chemical shift evolution and 1HN relaxation during signal acquisition both are significantly reduced by mutual compensation of the DD and CSA interactions. The reduction of the linewidths when compared with a conventional two-dimensional 1H,15N-correlation experiment was 60% and 40%, respectively, and the residual linewidths were 5 Hz for 15N and 15 Hz for 1HN at 4 degrees C. Because the ratio of the DD and CSA relaxation rates is nearly independent of the molecular size, a similar percentagewise reduction of the overall transverse relaxation rates is expected for larger proteins. For a 15N-labeled protein of 150 kDa at 750 MHz and 20 degrees C one predicts residual linewidths of 10 Hz for 15N and 45 Hz for 1HN, and for the corresponding uniformly 15N,2H-labeled protein the residual linewidths are predicted to be smaller than 5 Hz and 15 Hz, respectively. The TROSY principle should benefit a variety of multidimensional solution NMR experiments, especially with future use of yet somewhat higher polarizing magnetic fields than are presently available, and thus largely eliminate one of the key factors that limit work with larger molecules.Keywords
This publication has 33 references indexed in Scilit:
- Solution NMR Measurement of Amide Proton Chemical Shift Anisotropy in 15N-Enriched Proteins. Correlation with Hydrogen Bond LengthJournal of the American Chemical Society, 1997
- Protein Backbone Dynamics and 15N Chemical Shift Anisotropy from Quantitative Measurement of Relaxation Interference EffectsJournal of the American Chemical Society, 1996
- An Approach to the Structure Determination of Larger Proteins Using Triple Resonance NMR Experiments in Conjunction with Random Fractional DeuterationJournal of the American Chemical Society, 1996
- Assignment of 15N, 13Cα, 13Cβ, and HN Resonances in an 15N,13C,2H Labeled 64 kDa Trp Repressor−Operator Complex Using Triple-Resonance NMR Spectroscopy and 2H-DecouplingJournal of the American Chemical Society, 1996
- Multiple-Quantum Line Narrowing for Measurement of H.alpha.-H.beta. J Couplings in Isotopically Enriched ProteinsJournal of the American Chemical Society, 1995
- NMR – this other method for protein and nucleic acid structure determinationActa Crystallographica Section D-Biological Crystallography, 1995
- Nuclear Magnetic Resonance Solution Structure of the fushi tarazu Homeodomain from Drosophila and Comparison with the Antennapedia HomeodomainJournal of Molecular Biology, 1994
- Proton nuclear magnetic relaxation of nitrogen-15-labeled nucleic acids via dipolar coupling and chemical shift anisotropyJournal of the American Chemical Society, 1983
- Nuclear magnetic relaxation in coupled spin systemsProgress in Nuclear Magnetic Resonance Spectroscopy, 1978
- Spin—spin coupling and the conformational states of peptide systemsProgress in Nuclear Magnetic Resonance Spectroscopy, 1976