Author(s): Igor Tkach, Isabel Bejenke, Fabian Hecker, Annemarie Kehl, Müge Kasanmascheff, Igor Gromov, Ion Prisecaru, Peter Höfer, Markus Hiller, Marina Bennati
Abstract
We present and discuss the performance of 1H electron-nuclear double resonance (ENDOR) at 263 GHz/9.4 Tesla by employing a prototype, commercial quasi optical spectrometer. Basic instrumental features of the setup are described alongside a comprehensive characterization of the new ENDOR probe head design. The performance of three different ENDOR pulse sequences (Davies, Mims and CP-ENDOR) is evaluated using the 1H BDPA radical. A key feature of 263 GHz spectroscopy – the increase in orientiation selectivity in comparison with 94 GHz experiments – is discussed in detail. For this purpose, the resolution of 1H ENDOR spectra at 263 GHz is verified using a representative protein sample containing approximately 15 picomoles of a tyrosyl radical. Davies ENDOR spectra recorded at 5 K reveal previously obscured spectral features, which are interpreted by spectral simulations aided by DFT calculations. Our analysis shows that seven internal proton couplings are detectable for this specific radical if sufficient orientation selectivity is achieved. The results prove the fidelity of 263 GHz experiments in reporting orientation-selected 1H ENDOR spectra and demonstrate that new significant information can be uncovered in complex molecular systems, owing to the enhanced resolution combined with high absolute sensitivity and no compromise in acquisition time.
A novel THz-band double-beam gyrotron for high-field DNP-NMR spectroscopy
From The DNP-NMR Blog:
A novel THz-band double-beam gyrotron for high-field DNP-NMR spectroscopy
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Idehara, T., et al., A novel THz-band double-beam gyrotron for high-field DNP-NMR spectroscopy. Review of Scientific Instruments, 2017. 88(9): p. 094708.
http://dx.doi.org/10.1063/1.4997994
nmrlearner
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10-27-2017 05:34 PM
Effect of electron spectral diffusion on static dynamic nuclear polarization at 7 Tesla #DNPNMR
From The DNP-NMR Blog:
Effect of electron spectral diffusion on static dynamic nuclear polarization at 7 Tesla #DNPNMR
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Leavesley, A., et al., Effect of electron spectral diffusion on static dynamic nuclear polarization at 7 Tesla. Phys. Chem. Chem. Phys., 2017. 19(5): p. 3596-3605.
https://www.ncbi.nlm.nih.gov/pubmed/28094364
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06-02-2017 08:33 PM
[NMR paper] The determination of pair distance distribution by double electron-electron resonance: Regularization by the length of distance discretization with Monte Carlo calculations
The determination of pair distance distribution by double electron-electron resonance: Regularization by the length of distance discretization with Monte Carlo calculations
Publication date: Available online 2 June 2016
Source:Journal of Magnetic Resonance</br>
Author(s): Sergei A. Dzuba</br>
Pulsed double electron-electron resonance technique (DEER, or PELDOR) is applied to study conformations and aggregation of peptides, proteins, nucleic acids, and other macromolecules. For a pair of spin labels, experimental data allows for determination of their distance...
[NMR paper] Detection of the water-binding sites of the oxygen-evolving complex of Photosystem II using W-band 17O electron-electron double resonance-detected NMR spectroscopy.
Detection of the water-binding sites of the oxygen-evolving complex of Photosystem II using W-band 17O electron-electron double resonance-detected NMR spectroscopy.
http://www.bionmr.com//www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--pubs.acs.org-images-pubmed-acspubs.jpg Related Articles Detection of the water-binding sites of the oxygen-evolving complex of Photosystem II using W-band 17O electron-electron double resonance-detected NMR spectroscopy.
J Am Chem Soc. 2012 Oct 10;134(40):16619-34
Authors: Rapatskiy L, Cox N, Savitsky A, Ames WM, Sander J,...
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Journal club
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03-02-2013 11:45 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...
nmrlearner
Journal club
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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...
1H High Field Electron-Nuclear Double Resonance Spectroscopy at 263 GHz/9.4 Tesla
Linear Mode
