The amide proton exchange rates have been measured for the pike parvalbumin loaded either with calcium (PaCa2) or with magnesium (PaMg2) by using 2-D total correlation spectroscopy experiments. The differences in the exchange rates observed between these two species were unexpected when compared with the small conformational changes induced in parvalbumin by the Ca/Mg exchange. With the calcium-loaded protein (PaCa2), a significant difference was observed for the amide proton exchange rates of residues located in the N-terminal domain AB in contrast to the slower exchange rates that were observed in the CD and EF domains. Such a difference does not exist for PaMg2, where faster exchange rates are observed over all the sequence. Since amide proton exchange rates are the signature of the solvent's accessibility in proteins, we interpreted our results in terms of difference of the equilibria between 'closed-states' and 'opened-states' for individual amide protons of the protein when calcium was replaced by magnesium. The CD and EF domains, and to a lesser extent the AB domain, would be more rigid when the protein was loaded with calcium ions. For the magnesium-loaded parvalbumin (PaMg2) the faster exchange rates we observed could be rationalized by a more flexible structure than in the case of the PaCa2.
Measurement of amide hydrogen exchange rates with the use of radiation damping
Measurement of amide hydrogen exchange rates with the use of radiation damping
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...
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[NMR paper] NMR studies on Cu(II)-peptide complexes: exchange kinetics and determination of struc
NMR studies on Cu(II)-peptide complexes: exchange kinetics and determination of structures in solution.
Related Articles NMR studies on Cu(II)-peptide complexes: exchange kinetics and determination of structures in solution.
Mol Biosyst. 2005 May;1(1):79-84
Authors: Gaggelli E, Kozlowski H, Valensin D, Valensin G
The interaction of copper(II) with histidine containing peptides has recently acquired renewed interest following the established link between abnormal protein behaviour in neurodegenerative processes and unpaired copper homeostasis....
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[NMR paper] An NMR method for studying the kinetics of metal exchange in biomolecular systems.
An NMR method for studying the kinetics of metal exchange in biomolecular systems.
Related Articles An NMR method for studying the kinetics of metal exchange in biomolecular systems.
J Biomol NMR. 2002 Aug;23(4):303-9
Authors: Barbieri R, Hore PJ, Luchina C, Pierattelli R
The kinetics of lanthanide (III) exchange for calcium(II) in the C-terminal EF-hand of the protein calbindin D9k have been studied by one-dimensional (1D) stopped-flow NMR. By choosing a paramagnetic lanthanide (Ce3+), kinetics in the sub-second range can be easily measured....
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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.
Related Articles Amide proton hydrogen exchange rates for sperm whale myoglobin obtained from 15N-1H NMR spectra.
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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[NMR paper] Rapid amide proton exchange rates in peptides and proteins measured by solvent quench
Rapid amide proton exchange rates in peptides and proteins measured by solvent quenching and two-dimensional 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 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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[NMR paper] Comparison of amide proton exchange in reduced and oxidized Rhodobacter capsulatus cy
Comparison of amide proton exchange in reduced and oxidized Rhodobacter capsulatus cytochrome c2: a 1H-15N NMR study.
Related Articles Comparison of amide proton exchange in reduced and oxidized Rhodobacter capsulatus cytochrome c2: a 1H-15N NMR study.
J Biomol NMR. 1991 Jul;1(2):145-54
Authors: Gooley PR, Zhao D, MacKenzie NE
The hydrogen-deuterium exchange rates of the reduced and oxidized forms of Rhodobacter capsulatus cytochrome c2 were studied by 1H-15N homonuclear multiple quantum correlation spectroscopy. Minimal differences were...
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08-21-2010 11:16 PM
[NMR paper] Hydrogen exchange kinetics in a membrane protein determined by 15N NMR spectroscopy:
Hydrogen exchange kinetics in a membrane protein determined by 15N NMR spectroscopy: use of the INEPT experiment to follow individual amides in detergent-solubilized M13 coat protein.
Related Articles Hydrogen exchange kinetics in a membrane protein determined by 15N NMR spectroscopy: use of the INEPT experiment to follow individual amides in detergent-solubilized M13 coat protein.
Biochemistry. 1990 Jul 3;29(26):6303-13
Authors: Henry GD, Sykes BD
The coat protein of the filamentous coliphage M13 is a 50-residue polypeptide which spans the...
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Comparison of fast backbone dynamics at amide nitrogen and carbonyl sites in dematin
Abstract We perform a detailed comparison of fast backbone dynamics probed at amide nitrogen versus carbonyl carbon sites for dematin headpiece C-terminal domain (DHP) and its S74E mutant (DHPS74E). Carbonyl dynamics is probed via auto-correlated longitudinal rates and transverse Câ?²/Câ?²-Cα CSA/dipolar and Câ?²/Câ?²â??N CSA/dipolar cross-correlated rates, while 15N data are taken from a previous study. Resulting values of effective order parameters and internal correlation times support the conclusion that Câ?² relaxation reports on a different subset of fast motions compared to those...