Related ArticlesAn 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 usually employed to suppress cross-correlation between dipole-dipole and CSA relaxation mechanisms. For example, in a scalar-coupled two-spin X-H spin system the use of (1)H WALTZ16 decoupling or (1)H pulses applied at regularly spaced intervals leads to a significant overestimation of heteronuclear R(1)(rho) values. The problem is studied experimentally and theoretically for (15)N-(1)H and (13)C-(1)H spin pairs, and simple schemes are described which eliminate the artifacts. The approaches suggested are essential replacements of existing methodology if accurate dynamics parameters are to be extracted from spin-lock relaxation data sets.
Accurate measurement of one-bond H-X heteronuclear dipolar couplings in MAS solid-state NMR.
Accurate measurement of one-bond H-X heteronuclear dipolar couplings in MAS solid-state NMR.
Accurate measurement of one-bond H-X heteronuclear dipolar couplings in MAS solid-state NMR.
J Magn Reson. 2011 Mar 21;
Authors: Schanda P, Meier BH, Ernst M
The accurate experimental determination of dipolar-coupling constants for one-bond heteronuclear dipolar couplings in solids is a key for the quantification of the amplitudes of motional processes. Averaging of the dipolar coupling reports on motions on time scales up to the inverse of the coupling...
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04-13-2011 11:57 PM
Accurate Measurement of One-Bond H-X Heteronuclear Dipolar Couplings in MAS Solid-State NMR
Accurate Measurement of One-Bond H-X Heteronuclear Dipolar Couplings in MAS Solid-State NMR
Publication year: 2011
Source: Journal of Magnetic Resonance, In Press, Accepted Manuscript, Available online 21 March 2011</br>
Paul, Schanda , Beat H., Meier , Matthias, Ernst</br>
The accurate experimental determination of dipolar-coupling constants for one-bond heteronuclear dipolar couplings in solids is a key for the quantification of the amplitudes of motional processes. Averaging of the dipolar coupling reports on motions on time scales up to the inverse of the coupling constant, in...
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03-22-2011 07:30 AM
ROESY spin-lock power
I'm using roesyph.2 pulse sequence and I would like to know how to calculate spin-lock power in Hz for this experment.
Thnx
Justyna
sikorska.justyna
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03-10-2011 05:04 PM
[Question from NMRWiki Q&A forum] How to correctly set ROESY spin-lock power?
How to correctly set ROESY spin-lock power?
I'm using roesyph.2 pulse sequence (Bruker) and I would like to know how to calculate spin-lock power in Hz for this experiment. Thnx
Justyna
ps. I'm aware that for hard pulse it is 1/pw360, therefore can I assume that in this case it is 1/2*P25?
nmrlearner
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03-08-2011 04:10 PM
[Question from NMRWiki Q&A forum] ROESY spin-lock power
ROESY spin-lock power
I'm using roesyph.2 pulse sequence (Bruker) and I would like to know how to calculate spin-lock power in Hz for this experiment. Thnx
Justyna
ps. I'm aware that for hard pulse it is 1/pw360, therefore can I assume that in this case it is 1/2*P25?
nmrlearner
News from other NMR forums
0
01-17-2011 02:40 AM
15NH/D-SOLEXSY experiment for accurate measurement of amide solvent exchange rates: a
Abstract Amide solvent exchange rates are regarded as a valuable source of information on structure/dynamics of unfolded (disordered) proteins. Proton-based saturation transfer experiments, normally used to measure solvent exchange, are known to meet some serious difficulties. The problems mainly arise from the need to (1) manipulate water magnetization and (2) discriminate between multiple magnetization transfer pathways that occur within the proton pool. Some of these issues are specific to unfolded proteins. For example, the compensation scheme used to cancel the Overhauser effect in the...