Publication date: Available online 16 November 2013 Source:Journal of Magnetic Resonance
Author(s): Derek Marsh
Methods for determining inter-spin distances between nitroxide spin labels from dipolar couplings in the intermediate range (r 12 ? 1.1-2 nm) by CW-EPR are addressed. For nitroxide powder patterns, the assumption of unlike spins is a better approximation than assuming strong coupling between like spins. Methods that determine the average splitting in dipolar deconvolutions yield the mean value ? 1 / r 12 3 ? , and those that determine the dipolar contribution to the spectral second moment correspondingly yield ? 1 / r 12 6 ? . To relate these ensemble averages to the mean inter-spin distance ? r 12 ? requires knowledge of the distribution in r 12. Values of the inverse roots r eff , n = ? 1 / r 12 n ? - 1 / n always lie below ? r 12 ? . Consistent comparisons of literature data on double-labelled ? -helical peptides support this view. Evaluations of reff,n for Gaussian distributions in r 12 yield calibrations to determine ? r 12 ? for a given distribution width, ? r 12 . Graphical abstract
Conformational dynamics and distribution of nitroxide spin labels
Conformational dynamics and distribution of nitroxide spin labels
Publication date: Available online 18 April 2013
Source:Progress in Nuclear Magnetic Resonance Spectroscopy</br>
Author(s): Gunnar Jeschke</br>
Long-range distance measurements based on paramagnetic relaxation enhancement (PRE) in NMR, quantification of surface water dynamics near biomacromolecules by Overhauser dynamic nuclear polarization (DNP) and sensitivity enhancement by solid-state DNP all depend on introducing paramagnetic species into an otherwise diamagnetic NMR sample. The species can be...
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04-18-2013 10:12 PM
[NMR paper] Electron Spin Density on the Axial His Ligand of High-Spin and Low-Spin Nitrophorin 2 Probed by Heteronuclear NMR Spectroscopy.
Electron Spin Density on the Axial His Ligand of High-Spin and Low-Spin Nitrophorin 2 Probed by Heteronuclear NMR Spectroscopy.
http://www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--pubs.acs.org-images-pubmed-acspubs.jpg Related Articles Electron Spin Density on the Axial His Ligand of High-Spin and Low-Spin Nitrophorin 2 Probed by Heteronuclear NMR Spectroscopy.
Inorg Chem. 2013 Jan 17;
Authors: Abriata LA, Zaballa ME, Berry RE, Yang F, Zhang H, Walker FA, Vila AJ
Abstract
The electronic structure of heme proteins is exquisitely tuned...
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02-03-2013 10:19 AM
Effect of freezing conditions on distances and their distributions derived from Double Electron Electron Resonance (DEER): A study of doubly-spin-labeled T4 lysozyme
Effect of freezing conditions on distances and their distributions derived from Double Electron Electron Resonance (DEER): A study of doubly-spin-labeled T4 lysozyme
Publication year: 2012
Source:Journal of Magnetic Resonance, Volume 216</br>
Elka R. Georgieva, Aritro S. Roy, Vladimir M. Grigoryants, Petr P. Borbat, Keith A. Earle, Charles P. Scholes, Jack H. Freed</br>
Pulsed dipolar ESR spectroscopy, DEER and DQC, require frozen samples. An important issue in the biological application of this technique is how the freezing rate and concentration of cryoprotectant...
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03-13-2012 03:33 PM
Effect of Freezing Conditions on Distances and Their Distributions Derived from Double Electron Electron Resonance (DEER): A Study of Doubly-Spin-Labeled T4 Lysozyme
Effect of Freezing Conditions on Distances and Their Distributions Derived from Double Electron Electron Resonance (DEER): A Study of Doubly-Spin-Labeled T4 Lysozyme
Publication year: 2012
Source: Journal of Magnetic Resonance, Available online 24 January 2012</br>
Elka R.*Georgieva, Aritro S.*Roy, Vladimir M.*Grigoryants, Petr P.*Borbat, Keith A.*Earle, ...</br>
Pulsed dipolar ESR spectroscopy, DEER and DQC, require frozen samples. An important issue in the biological application of this technique is how the freezing rate and concentration of cryoprotectant could possibly affect the...
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01-25-2012 08:56 AM
[CNS Yahoo group] Distances
Distances
Dear All, * I am resolving*a structure of DNA:RNA hybrid. I want to ask if the hydrogen bonding follow the same rules and distances of DNA:DNA or RNA:RNA
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03-17-2011 06:30 PM
[NMR paper] Spin labels as a tool to identify and characterize protein-ligand interactions by NMR
Spin labels as a tool to identify and characterize protein-ligand interactions by NMR spectroscopy.
Related Articles Spin labels as a tool to identify and characterize protein-ligand interactions by NMR spectroscopy.
Chembiochem. 2002 Mar 1;3(2-3):167-73
Authors: Jahnke W
NMR spectroscopy based discovery and optimization of lead compounds for a given molecular target requires the development of methods with maximum sensitivity and robustness. It is shown here that organic nitroxide radicals ("spin labels") can be used to boost the sensitivity...
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11-24-2010 08:49 PM
[NMR paper] An NMR investigation of the conformational effect of nitroxide spin labels on Ala-ric
An NMR investigation of the conformational effect of nitroxide spin labels on Ala-rich helical peptides.
Related Articles An NMR investigation of the conformational effect of nitroxide spin labels on Ala-rich helical peptides.
J Magn Reson. 1998 Apr;131(2):248-53
Authors: Bolin KA, Hanson P, Wright SJ, Millhauser GL
Nitroxide spin labels, in conjunction with electron spin resonance (ESR) experiments, are extensively employed to probe the structure and dynamics of biomolecules. One of the most ubiquitous spin labeling reagents is the...
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11-17-2010 11:06 PM
[NMR Sparky Yahoo group] Assignment distances for methyls
Assignment distances for methyls
... Hi Jessica, The Sparky assignment distance dialog isn't smart enough to match atom names using patterns (e.g. HB*), it only handles exact matches.
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Intermediate Dipolar Distances from Spin Labels
Highlights
Linear Mode
