Many regulatory RNAs undergo dynamic exchanges that are crucial for their biological functions and NMR spectroscopy is a versatile tool for monitoring dynamic motions of biomolecules. Meaningful information on biomolecular dynamics requires an accurate measurement of relaxation parameters such as longitudinal (R1) rates, transverse (R2) rates and heteronuclear Overhauser effect (hNOE). However, earlier studies have shown that the large 13Câ??13C interactions complicate analysis of the carbon relaxation parameters. To investigate the effect of 13Câ??13C interactions on RNA dynamic studies, we performed relaxation measurements on various RNA samples with different labeling patterns and compared these measurements with the computational simulations. For uniformly labeled samples, contributions of the neighboring carbon to R1 measurements were observed. These contributions increased with increasing magnetic field and overall correlation time (\({\tau }_{\text{C}}\)) for R1 rates, necessitating more careful analysis for uniformly labeled large RNAs. In addition, the hNOE measurements were also affected by the adjacent carbon nuclei. Unlike R1 rates, R1Ï? rates showed relatively good agreement between uniformly- and site-selectively labeled samples, suggesting no dramatic effect from their attached carbon, in agreement with previous observations. Overall, having more accurate rate measurements avoids complex analysis and will be a key for interpreting 13C relaxation rates for molecular motion that can provide valuable insights into cellular molecular recognition events.
Carbon-carbon spin-spin coupling constants: Practical applications of theoretical calculations
Carbon-carbon spin-spin coupling constants: Practical applications of theoretical calculations
Publication date: April 2018
Source:Progress in Nuclear Magnetic Resonance Spectroscopy, Volume 105</br>
Author(s): Leonid B. Krivdin</br>
Practical applications of theoretical calculations of carbon-carbon spin-spin coupling constants in particular classes of organic and bioorganic molecules are reviewed, concentrating mainly on saturated, unsaturated, aromatic and heteroaromatic compounds and their functional derivatives as well as on carbohydrates and natural...
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04-14-2018 01:49 PM
[NMR paper] Cross-Correlated Relaxation of Dipolar Coupling and Chemical-Shift Anisotropy in Magic-Angle Spinning R1? NMR Measurements: Application to Protein Backbone Dynamics Measurements.
Cross-Correlated Relaxation of Dipolar Coupling and Chemical-Shift Anisotropy in Magic-Angle Spinning R1? NMR Measurements: Application to Protein Backbone Dynamics Measurements.
Cross-Correlated Relaxation of Dipolar Coupling and Chemical-Shift Anisotropy in Magic-Angle Spinning R1? NMR Measurements: Application to Protein Backbone Dynamics Measurements.
J Phys Chem B. 2016 Aug 8;
Authors: Kurauskas V, Weber E, Hessel A, Ayala I, Marion D, Schanda P
Abstract
Transverse relaxation rate measurements in MAS solid-state NMR...
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08-09-2016 02:42 PM
Asynchronous through-bond homonuclear isotropic mixing: application to carbonâ??carbon transfer in perdeuterated proteins under MAS
Asynchronous through-bond homonuclear isotropic mixing: application to carbonâ??carbon transfer in perdeuterated proteins under MAS
Abstract
Multiple-bond carbonâ??carbon homonuclear mixing is a hurdle in extensively deuterated proteins and under fast MAS due to the absence of an effective proton dipolar-coupling network. Such conditions are now commonly employed in solid-state NMR spectroscopy. Here, we introduce an isotropic homonuclear 13Câ??13C through-bond mixing sequence, MOCCA, for the solid state. Even though applied under MAS, this scheme...
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08-29-2015 09:18 PM
Protein resonance assignment at MAS frequencies approaching 100Â*kHz: a quantitative comparison of J-coupling and dipolar-coupling-based transfer methods
Protein resonance assignment at MAS frequencies approaching 100Â*kHz: a quantitative comparison of J-coupling and dipolar-coupling-based transfer methods
Abstract
We discuss the optimum experimental conditions to obtain assignment spectra for solid proteins at magic-angle spinning (MAS) frequencies around 100Â*kHz. We present a systematic examination of the MAS dependence of the amide proton T 2â?² times and a site-specific comparison of T 2â?² at 93Â*kHz versus 60Â*kHz MAS frequency. A...
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08-13-2015 02:00 PM
Long-Range Proton-Carbon Coupling Constants: NMR methods and applications
Long-Range Proton-Carbon Coupling Constants: NMR methods and applications
Publication date: Available online 20 July 2013
Source:Progress in Nuclear Magnetic Resonance Spectroscopy</br>
Author(s): Teodor Parella , Juan Félix Espinosa</br>
A general review of novel NMR methods to measure heteronuclear long-range proton-carbon coupling constants ( n J CH ; n>1) in small molecules is made. NMR experiments are classified in terms of NMR pulse scheme and cross-peak nature. A discussion about simplicity, general applicability and accuracy for each...
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07-20-2013 11:27 AM
The Use of Residual Dipolar Coupling in Studying Proteins by NMR.
The Use of Residual Dipolar Coupling in Studying Proteins by NMR.
The Use of Residual Dipolar Coupling in Studying Proteins by NMR.
Top Curr Chem. 2011 Sep 28;
Authors: Chen K, Tjandra N
Abstract
The development of residual dipolar coupling (RDC) in protein NMR spectroscopy, over a decade ago, has become a useful and almost routine tool for accurate protein solution structure determination. RDCs provide orientation information of magnetic dipole-dipole interaction vectors within a common reference frame. Its measurement requires a...
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09-30-2011 06:00 AM
The Use of Residual Dipolar Coupling in Studying Proteins by NMR.
The Use of Residual Dipolar Coupling in Studying Proteins by NMR.
The Use of Residual Dipolar Coupling in Studying Proteins by NMR.
Top Curr Chem. 2011 Sep 28;
Authors: Chen K, Tjandra N
Abstract
The development of residual dipolar coupling (RDC) in protein NMR spectroscopy, over a decade ago, has become a useful and almost routine tool for accurate protein solution structure determination. RDCs provide orientation information of magnetic dipole-dipole interaction vectors within a common reference frame. Its measurement requires a...
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09-30-2011 05:59 AM
[Question from NMRWiki Q&A forum] How can I calculate a carbon-proton coupling constant for a molecule?
How can I calculate a carbon-proton coupling constant for a molecule?
I'm trying to explain a missing HMBC peak, and having a coupling constant less than 10 Hz would do that nicely. It's a formamidine derivative with a 3 bond correlation N=CHNC The C is a quaternary carbon in a benzene ring. Any help would be appreciated.
Check if somebody has answered this question on NMRWiki QA forum
Deleterious effects of carbonâ??carbon dipolar coupling on RNA NMR dynamics
Linear Mode
