Active bandwidth and global quality factor are the two main metrics used to quantitatively compare the performance of TOCSY mixing sequences. Active bandwidth refers to the spectral region over which at least 50Â*% of the magnetization is transferred via a coupling. Global quality factor scores mixing sequences according to the worst-case transfer over a range of possible mixing times and chemical shifts. Both metrics reward high transfer efficiency away from the main diagonal of a two-dimensional spectrum. They can therefore be used to design mixing sequences that will function favorably in experiments. Here, we develop optimization methods tailored to these two metrics, including precise control of off-diagonal cross peak buildup rates. These methods produce square shaped transfer efficiency profiles, directly matching the desirable properties that the metrics are intended to measure. The optimization methods are analytical, rather than numerical. The two resultant shaped pulses have significantly higher active bandwidth and quality factor, respectively, than all other known sequences. They are therefore highly suitable for use in NMR spectroscopy. We include experimental verification of these improved waveforms on small molecule and protein samples.
[NMR paper] Micro-scale NMR Experiments for Monitoring the Optimization of Membrane Protein Solutions for Structural Biology.
Micro-scale NMR Experiments for Monitoring the Optimization of Membrane Protein Solutions for Structural Biology.
Micro-scale NMR Experiments for Monitoring the Optimization of Membrane Protein Solutions for Structural Biology.
Bio Protoc. 2015 Jul 20;5(14)
Authors: Horst R, Wüthrich K
Abstract
Reconstitution of integral membrane proteins (IMP) in aqueous solutions of detergent micelles has been extensively used in structural biology, using either X-ray crystallography or NMR in solution. Further progress could be achieved by...
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04-15-2016 05:06 PM
Level Anti-Crossings are a Key Factor for Understanding para-Hydrogen-Induced Hyperpolarization in SABRE Experiments
From The DNP-NMR Blog:
Level Anti-Crossings are a Key Factor for Understanding para-Hydrogen-Induced Hyperpolarization in SABRE Experiments
Pravdivtsev, A.N., et al., Level Anti-Crossings are a Key Factor for Understanding para-Hydrogen-Induced Hyperpolarization in SABRE Experiments. ChemPhysChem, 2013. 14(14): p. 3327-3331.
http://www.ncbi.nlm.nih.gov/pubmed/23959909
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04-16-2014 11:09 PM
Optimization of an absolute sensitivity in a glassy matrix during DNP-enhanced multidimensional solid-state NMR experiments
From The DNP-NMR Blog:
Optimization of an absolute sensitivity in a glassy matrix during DNP-enhanced multidimensional solid-state NMR experiments
Takahashi, H., et al., Optimization of an absolute sensitivity in a glassy matrix during DNP-enhanced multidimensional solid-state NMR experiments. J Magn Reson, 2013. 239C(0): p. 91-99.
http://www.ncbi.nlm.nih.gov/pubmed/24480716
[Question from NMRWiki Q&A forum] Question about bandwidth
Question about bandwidth
Is acquisition bandwidth and receiver bandwidth the same?? am confused with the terminology....please clarify....thanks
Check if somebody has answered this question on NMRWiki QA forum
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02-07-2011 07:53 PM
HNCA-TOCSY-CANH experiments with alternate 13C-12C labeling: a set of 3D experiment w
HNCA-TOCSY-CANH experiments with alternate 13C-12C labeling: a set of 3D experiment with unique supra-sequential information for mainchain resonance assignment
Abstract Described here is a set of three-dimensional (3D) NMR experiments that rely on CACA-TOCSY magnetization transfer via the weak
3 \textJ\textCa\textCa coupling. These pulse sequences, which resemble recently described 13C detected CACA-TOCSY (Takeuchi et al. 2010) experiments, are recorded in 1H2O, and use 1H excitation and detection. These experiments require alternate 13C-12C labeling together with perdeuteration,...
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11-27-2010 07:34 PM
[NMR paper] Exploring the active site of human factor Xa protein by NMR screening of small molecu
Exploring the active site of human factor Xa protein by NMR screening of small molecule probes.
Related Articles Exploring the active site of human factor Xa protein by NMR screening of small molecule probes.
Org Biomol Chem. 2003 Dec 7;1(23):4235-41
Authors: Fielding L, Fletcher D, Rutherford S, Kaur J, Mestres J
A collection of small molecules (MW < 350 Da) was screened for binding to human factor Xa using saturation transfer difference NMR spectroscopy to detect binding. The NMR screening experiments identified four hits. Binding isotherms...
Analytical optimization of active bandwidth and quality factor for TOCSY experiments in NMR spectroscopy
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