Fast magic-angle spinning (>60Â*kHz) has many advantages but makes spin-diffusion-type protonâ??proton long-range polarization transfer inefficient and highly dependent on chemical-shift offset. Using 100%-HN-[2H,13C,15N]-ubiquitin as a model substance, we quantify the influence of the chemical-shift difference on the spin diffusion between proton spins and compare two experiments which lead to an improved chemical-shift compensation of the transfer: rotating-frame spin diffusion and a new experiment, reverse amplitude-modulated MIRROR. Both approaches enable broadband spin diffusion, but the application of the first variant is limited due to fast spin relaxation in the rotating frame. The reverse MIRROR experiment, in contrast, is a promising candidate for the determination of structurally relevant distance restraints. The applied tailored rf-irradiation schemes allow full control over the range of recoupled chemical shifts and efficiently drive spin diffusion. Here, the relevant relaxation time is the larger longitudinal relaxation time, which leads to a higher signal-to-noise ratio in the spectra.
[NMR paper] Relaxation-compensated difference spin diffusion NMR for detecting (13)C- (13)C long-range correlations in proteins and polysaccharides.
Relaxation-compensated difference spin diffusion NMR for detecting (13)C- (13)C long-range correlations in proteins and polysaccharides.
Relaxation-compensated difference spin diffusion NMR for detecting (13)C- (13)C long-range correlations in proteins and polysaccharides.
J Biomol NMR. 2014 Dec 16;
Authors: Wang T, Williams JK, Schmidt-Rohr K, Hong M
Abstract
The measurement of long-range distances remains a challenge in solid-state NMR structure determination of biological macromolecules. In 2D and 3D correlation spectra of...
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12-17-2014 09:43 PM
Relaxation-compensated difference spin diffusion NMR for detecting 13 Câ?? 13 C long-range correlations in proteins and polysaccharides
Relaxation-compensated difference spin diffusion NMR for detecting 13 Câ?? 13 C long-range correlations in proteins and polysaccharides
Abstract
The measurement of long-range distances remains a challenge in solid-state NMR structure determination of biological macromolecules. In 2D and 3D correlation spectra of uniformly 13C-labeled biomolecules, inter-residue, inter-segmental, and intermolecular 13Câ??13C cross peaks that provide important long-range distance constraints for three-dimensional structures often overlap with short-range cross peaks...
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12-15-2014 03:31 PM
[NMR paper] Water proton spin saturation affects measured protein backbone 15N spin relaxation rates
From Mendeley Biomolecular NMR group:
Water proton spin saturation affects measured protein backbone 15N spin relaxation rates
Journal of Magnetic Resonance (2011). Volume: 213, Issue: 1. Pages: 151-157. Kang Chen, Nico Tjandra et al.
Published using Mendeley: The library management tool for researchers
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11-22-2012 11:49 AM
[NMR paper] Water proton spin saturation affects measured protein backbone 15N spin relaxation rates
From Mendeley Biomolecular NMR group:
Water proton spin saturation affects measured protein backbone 15N spin relaxation rates
Journal of Magnetic Resonance (2011). Volume: 213, Issue: 1. Pages: 151-157. Kang Chen, Nico Tjandra et al.
Published using Mendeley: The reference manager for researchers
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10-12-2012 09:58 AM
[NMR paper] Water proton spin saturation affects measured protein backbone 15N spin relaxation rates
From Mendeley Biomolecular NMR group:
Water proton spin saturation affects measured protein backbone 15N spin relaxation rates
Journal of Magnetic Resonance (2011). Volume: 213, Issue: 1. Pages: 151-157. Kang Chen, Nico Tjandra et al.
Published using Mendeley: The digital library for researchers
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08-24-2012 08:01 PM
Water proton spin saturation affects measured protein backboneN spin relaxation rates
Water proton spin saturation affects measured protein backboneN spin relaxation rates
Publication year: 2011
Source: Journal of Magnetic Resonance, Available online 1 October 2011</br>
Kang*Chen, Nico*Tjandra</br>
Protein backboneN NMR spin relaxation rates are useful in characterizing the protein dynamics and structures. To observe the protein nuclear-spin resonances a pulse sequence has to include a water suppression scheme. There are two commonly employed methods, saturating or dephasing the water spins with pulse field gradients and keeping them unperturbed with flip-back pulses....
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10-02-2011 08:25 AM
Optimum levels of exchangeable protons in perdeuterated proteins for proton detection in MAS solid-state NMR spectroscopy
Optimum levels of exchangeable protons in perdeuterated proteins for proton detection in MAS solid-state NMR spectroscopy
Abstract We present a systematic study of the effect of the level of exchangeable protons on the observed amide proton linewidth obtained in perdeuterated proteins. Decreasing the amount of D2O employed in the crystallization buffer from 90 to 0%, we observe a fourfold increase in linewidth for both 1H and 15N resonances. At the same time, we find a gradual increase in the signal-to-noise ratio (SNR) for 1Hâ??15N correlations in dipolar coupling based experiments for...
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01-09-2011 12:46 PM
[NMR paper] Anisotropic rotational diffusion of perdeuterated HIV protease from 15N NMR relaxatio
Anisotropic rotational diffusion of perdeuterated HIV protease from 15N NMR relaxation measurements at two magnetic fields.
Related Articles Anisotropic rotational diffusion of perdeuterated HIV protease from 15N NMR relaxation measurements at two magnetic fields.
J Biomol NMR. 1996 Oct;8(3):273-84
Authors: Tjandra N, Wingfield P, Stahl S, Bax A
15N NMR relaxation times in perdeuterated HIV-1 protease, complexed with the sub-nanomolar inhibitor DMP323, have been measured at 600 and 360 MHz 1H frequency. The relative magnitudes of the principal...
Accelerating proton spin diffusion in perdeuterated proteins at 100Â*kHz MAS
Linear Mode
