Publication date: Available online 28 June 2014 Source:Journal of Magnetic Resonance
Author(s): Nicolas D. Werbeck , D. Flemming Hansen
The equations that describe the time-evolution of transverse and longitudinal 15N magnetisations in tetrahedral ammonium ions, 15NH4 +, are derived from the Bloch-Wangsness-Redfield density operator relaxation theory. It is assumed that the relaxation of the spin-states is dominated by (1) the intra-molecular 15N-1H and 1H-1H dipole-dipole interactions and (2) interactions of the ammonium protons with remote spins, which also include the contribution to the relaxations that arise from the exchange of the ammonium protons with the bulk solvent. The dipole-dipole cross-correlated relaxation mechanisms between each of the 15N-1H and 1H-1H interactions are explicitly taken into account in the derivations. An application to 15N-ammonium bound to a 41 kDa domain of the protein DnaK is presented, where a comparison between experiments and simulations show that the ammonium ion rotates rapidly within its binding site with a local correlation time shorter than approximately 1 ns. The theoretical framework provided here forms the basis for further investigations of dynamics of AX4 spin systems, with ammonium ions in solution and bound to proteins of particular interest. Graphical abstract
Full relaxation matrix analysis of apparent cross-correlated relaxation rates in four-spin systems
Full relaxation matrix analysis of apparent cross-correlated relaxation rates in four-spin systems
January 2013
Publication year: 2013
Source:Journal of Magnetic Resonance, Volume 226</br>
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Cross-correlated relaxation (CCR) rates are an established tool for the extraction of relative bond orientations in biomolecules in solution. CCR between dipolar interactions in four-spin systems is a particularly well-suited mechanism. In this paper, a simple approach to analyze systematic experimental errors is formulated in a subspace of the complete four-spin Hilbert space....
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12-15-2012 09:51 AM
Full relaxation matrix analysis of apparent cross-correlated relaxation rates in four-spin systems
Full relaxation matrix analysis of apparent cross-correlated relaxation rates in four-spin systems
Available online 12 November 2012
Publication year: 2012
Source:Journal of Magnetic Resonance</br>
</br>
Cross-correlated relaxation (CCR) rates are an established tool for the extraction of relative bond orientations in biomolecules in solution. CCR between dipolar interactions in four-spin systems is a particularly well-suited mechanism. In this paper, a simple approach to analyze systematic experimental errors is formulated in a subspace of the complete four-spin...
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12-01-2012 06:10 PM
Full relaxation matrix analysis of apparent cross-correlated relaxation rates in four-spin systems
Full relaxation matrix analysis of apparent cross-correlated relaxation rates in four-spin systems
Publication year: 2012
Source:Journal of Magnetic Resonance</br>
Beat Vögeli</br>
Cross-correlated relaxation (CCR) rates are an established tool for the extraction of relative bond orientations in biomolecules in solution. CCR between dipolar interactions in four-spin systems is a particularly well-suited mechanism. In this paper, a simple approach to analyze systematic experimental errors is formulated in a subspace of the complete four-spin Hilbert space. It is shown...
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11-13-2012 07:30 AM
13C relaxation experiments for aromatic side chains employing longitudinal- and transverse-relaxation optimized NMR spectroscopy
13C relaxation experiments for aromatic side chains employing longitudinal- and transverse-relaxation optimized NMR spectroscopy
Abstract Aromatic side chains are prevalent in protein binding sites, perform functional roles in enzymatic catalysis, and form an integral part of the hydrophobic core of proteins. Thus, it is of great interest to probe the conformational dynamics of aromatic side chains and its response to biologically relevant events. Indeed, measurements of 13C relaxation rates in aromatic moieties have a long history in biomolecular NMR, primarily in the context of...
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07-05-2012 04:13 AM
Relaxation theory of nuclear singlet states in two spin-1/2 systems
Relaxation theory of nuclear singlet states in two spin-1/2 systems
Publication year: 2010
Source: Progress in Nuclear Magnetic Resonance Spectroscopy, Volume 56, Issue 3, April 2010, Pages 217-231</br>
Giuseppe*Pileio</br>
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09-13-2011 09:15 PM
Continuous-wave EPR at 275 GHz: Application to high-spin Fe3+ systems
Continuous-wave EPR at 275 GHz: Application to high-spin Fe3+ systems
Publication year: 2011
Source: Journal of Magnetic Resonance, In Press, Accepted Manuscript, Available online 11 March 2011</br>
G., Mathies , H., Blok , J.A.J.M., Disselhorst , P., Gast , H., van der Meer , ...</br>
The 275 GHz electron-paramagnetic-resonance spectrometer we reported on in 2004 has been equipped with a new probe head, which contains a cavity especially designed for operation in continuous-wave mode. The sensitivity and signal stability that is achieved with this new probe head is illustrated...
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03-12-2011 05:21 PM
[NMR paper] An NMR experiment for the accurate measurement of heteronuclear spin-lock relaxation
An NMR experiment for the accurate measurement of heteronuclear spin-lock relaxation rates.
Related Articles An NMR experiment for the accurate measurement of heteronuclear spin-lock relaxation rates.
J Am Chem Soc. 2002 Sep 11;124(36):10743-53
Authors: Korzhnev DM, Skrynnikov NR, Millet O, Torchia DA, Kay LE
Rotating-frame relaxation rates, R(1)(rho), are often measured in NMR studies of protein dynamics. We show here that large systematic errors can be introduced into measured values of heteronuclear R(1)(rho) rates using schemes which are...
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11-24-2010 08:58 PM
[NMR paper] Application of cross-correlated NMR spin relaxation to the zinc-finger protein CRP2(L
Application of cross-correlated NMR spin relaxation to the zinc-finger protein CRP2(LIM2): evidence for collective motions in LIM domains.
Related Articles Application of cross-correlated NMR spin relaxation to the zinc-finger protein CRP2(LIM2): evidence for collective motions in LIM domains.
Biochemistry. 2001 Aug 14;40(32):9596-604
Authors: Schüler W, Kloiber K, Matt T, Bister K, Konrat R
The solution structure of quail CRP2(LIM2) was significantly improved by using an increased number of NOE constraints obtained from a 13C,15N-labeled...