Abstract A simple method for measuring amide hydrogen exchange rates is presented, which is based on the selective inversion of water magnetization with the use of radiation damping. Simulations show that accurate exchange rates can be measured despite the complications of radiation damping and cross relaxation to the exchange process between amide and water protons. This method cannot eliminate the contributions of the exchange-relayed NOE and direct NOE to the measured exchange rates, but minimize the direct NOE contribution. In addition, the amides with a significant amount of such indirect contributions are possible to be identified from the shape of the exchange peak intensity profiles or/and from the apparent relaxation rates of amide protons which are extracted from fitting the intensity profiles to an equation established here for our experiment. The method was tested on ubiquitin and also applied to an acyl carrier protein. The amide exchange rates for the acyl carrier protein at two pHs indicate that the entire protein is highly dynamic on the second timescale. Low protection factors for the residues in the regular secondary structural elements also suggest the presence of invisible unfolded species. The highly dynamic nature of the acyl carrier protein may be crucial for its interactions with its substrate and enzymes.
Content Type Journal Article
Category Article
Pages 151-162
DOI 10.1007/s10858-011-9549-6
Authors
Jing-Song Fan, Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore, 117543 Singapore
Jackwee Lim, Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore, 117543 Singapore
Binhan Yu, Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore, 117543 Singapore
Daiwen Yang, Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore, 117543 Singapore
Radiation Damping on Cryoprobes
Radiation Damping on Cryoprobes
Publication year: 2011
Source: Journal of Magnetic Resonance, Available online 9 September 2011</br>
Dmitry*Shishmarev, Gottfried*Otting</br>
Radiation damping on 600 and 800 MHz cryoprobes was investigated. The phase angle ? between a vector 90phase shifted to the precessing magnetization and the rf field induced in the coil was found to depend markedly on whether an FID was being acquired or not. The magnitude of the radiation-damping field was sufficiently strong to restore 95% of the equilibrium water magnetization of a 90% H2O sample in a 5 mm...
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[NMR paper] Amide proton hydrogen exchange rates for sperm whale myoglobin obtained from 15N-1H N
Amide proton hydrogen exchange rates for sperm whale myoglobin obtained from 15N-1H NMR spectra.
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Protein Sci. 2000 Jan;9(1):186-93
Authors: Cavagnero S, Thériault Y, Narula SS, Dyson HJ, Wright PE
The hydrogen exchange behavior of exchangeable protons in proteins can provide important information for understanding the principles of protein structure and function. The positions and exchange rates of the slowly-exchanging amide...
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11-18-2010 09:15 PM
[NMR paper] Stopped-flow NMR measurement of hydrogen exchange rates in reduced horse cytochrome c
Stopped-flow NMR measurement of hydrogen exchange rates in reduced horse cytochrome c under strongly destabilizing conditions.
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Proteins. 1998 Aug 1;32(2):241-7
Authors: Bhuyan AK, Udgaonkar JB
A procedure to measure exchange rates of fast exchanging protein amide hydrogens by time-resolved NMR spectroscopy following in situ initiation of the reaction by diluting a native protein solution into an...
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11-17-2010 11:15 PM
Quantification of protein backbone hydrogen-deuterium exchange rates by solid state N
Quantification of protein backbone hydrogen-deuterium exchange rates by solid state NMR spectroscopy
Abstract We present the quantification of backbone amide hydrogen-deuterium exchange rates (HDX) for immobilized proteins. The experiments make use of the deuterium isotope effect on the amide nitrogen chemical shift, as well as on proton dilution by deuteration. We find that backbone amides in the microcrystalline α-spectrin SH3 domain exchange rather slowly with the solvent (with exchange rates negligible within the individual 15Nâ??T 1 timescales). We observed chemical exchange for 6...
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10-27-2010 08:51 AM
Quantification of protein backbone hydrogen-deuterium exchange rates by solid state N
Quantification of protein backbone hydrogen-deuterium exchange rates by solid state NMR spectroscopy.
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J Biomol NMR. 2010 Oct 20;
Authors: Del Amo JM, Fink U, Reif B
We present the quantification of backbone amide hydrogen-deuterium exchange rates (HDX) for immobilized proteins. The experiments make use of the deuterium isotope effect on the amide nitrogen chemical shift, as well as on proton dilution by deuteration. We find that...
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[NMR paper] Human recombinant [C22A] FK506-binding protein amide hydrogen exchange rates from mas
Human recombinant FK506-binding protein amide hydrogen exchange rates from mass spectrometry match and extend those from NMR.
http://www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--www3.interscience.wiley.com-aboutus-images-wiley_interscience_pubmed_logo_FREE_120x27.gif http://www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--www.pubmedcentral.nih.gov-corehtml-pmc-pmcgifs-pubmed-pmc.gif Related Articles Human recombinant FK506-binding protein amide hydrogen exchange rates from mass spectrometry match and extend those from NMR.
Protein Sci. 1997 Oct;6(10):2203-17
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[NMR paper] Rapid amide proton exchange rates in peptides and proteins measured by solvent quench
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http://www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--www3.interscience.wiley.com-aboutus-images-wiley_interscience_pubmed_logo_FREE_120x27.gif http://www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--www.pubmedcentral.nih.gov-corehtml-pmc-pmcgifs-pubmed-pmc.gif Related Articles Rapid amide proton exchange rates in peptides and proteins measured by solvent quenching and two-dimensional NMR.
Protein Sci. 1995 Apr;4(4):804-14
Authors: Zhang YZ,...
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08-22-2010 03:41 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...