Change search
ReferencesLink to record
Permanent link

Direct link
Spectral density mapping at multiple magnetic fields suitable for C-13 NMR relaxation studies
Show others and affiliations
Number of Authors: 12
2016 (English)In: Journal of magnetic resonance (San Diego, Calif. 1997: Print), ISSN 1090-7807, E-ISSN 1096-0856, Vol. 266, 23-40 p.Article in journal (Refereed) Published
Abstract [en]

Standard spectral density mapping protocols, well suited for the analysis of N-15 relaxation rates, introduce significant systematic errors when applied to C-13 relaxation data, especially if the dynamics is dominated by motions with short correlation times (small molecules, dynamic residues of macromolecules). A possibility to improve the accuracy by employing cross-correlated relaxation rates and on measurements taken at several magnetic fields has been examined. A suite of protocols for analyzing such data has been developed and their performance tested. Applicability of the proposed protocols is documented in two case studies, spectral density mapping of a uniformly labeled RNA hairpin and of a selectively labeled disaccharide exhibiting highly anisotropic tumbling. Combination of auto- and cross-correlated relaxation data acquired at three magnetic fields was applied in the former case in order to separate effects of fast motions and conformational or chemical exchange. An approach using auto-correlated relaxation rates acquired at five magnetic fields, applicable to anisotropically moving molecules, was used in the latter case. The results were compared with a more advanced analysis of data obtained by interpolation of auto-correlated relaxation rates measured at seven magnetic fields, and with the spectral density mapping of cross-correlated relaxation rates. The results showed that sufficiently accurate values of auto- and cross-correlated spectral density functions at zero and C-13 frequencies can be obtained from data acquired at three magnetic fields for uniformly C-13-labeled molecules with a moderate anisotropy of the rotational diffusion tensor. Analysis of auto-correlated relaxation rates at five magnetic fields represents an alternative for molecules undergoing highly anisotropic motions.

Place, publisher, year, edition, pages
2016. Vol. 266, 23-40 p.
Keyword [en]
Nuclear magnetic resonance, Relaxation, Spectral density function, Magnetic field, Nucleic acids, Carbohydrates
National Category
Biological Sciences Physical Sciences Chemical Sciences
URN: urn:nbn:se:su:diva-130855DOI: 10.1016/j.jmr.2016.02.016ISI: 000375510100004PubMedID: 27003380OAI: diva2:934848
Available from: 2016-06-09 Created: 2016-06-07 Last updated: 2016-06-09Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textPubMed

Search in DiVA

By author/editor
Kowalewski, JozefWidmalm, Göran
By organisation
Department of Materials and Environmental Chemistry (MMK)Department of Organic Chemistry
In the same journal
Journal of magnetic resonance (San Diego, Calif. 1997: Print)
Biological SciencesPhysical SciencesChemical Sciences

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 2 hits
ReferencesLink to record
Permanent link

Direct link