Related ArticlesA two-dimensional NMR study of exchange behavior of amide hydrogens in a lysozyme derivative with an extra cross-link between Glu35 and Trp108--quenching of cooperative fluctuations and effects on the protein stability.
Biopolymers. 1997 Feb;41(2):131-43
Authors: Noda Y, Fukuda Y, Segawa S
Two-dimensional nmr spectra [correlated spectroscopy (COSY), homonuclear Hartmann-Hahn (HOHAHA), nuclear Overhauser effect spectroscopy (NOESY)] have been observed for cross-linked lysozyme, a chemically modified lysozyme derivative with an extra ester cross-link between residues E35 and W108. Eight shifted cross-peaks were found in the fingerprint region of COSY spectra. By searching COSY, HOHAHA and NOESY spectra, they have been assigned to A32, E35, S36, 158, A107, W108, V109, and A110. The NOE connectivities (dNN and d alpha N) found for the cross-linked lysozyme are quite similar to those for the intact lysozyme. Exchange behavior of amide hydrogens has been studied for both intact and cross-linked lysozymes by observing the fingerprint region of COSY spectra. Hydrogen exchange reactions were carried out at pH 7.0 and at several temperatures. There exist 41 amide hydrogens whose exchange reactions are detectable under this experimental condition. Not only exchange rates but also their activation enthalpies were determined for individual amide hydrogens. They are classified into two groups, which are called categories III and IV. Category III hydrogens are distributed in relatively flexible peripheral parts of protein, and category IV hydrogens are deeply buried in the core region of protein. Category III hydrogens are exchanged through localized unfolding around their sites with a low activation enthalpy ranging from 10 to 25 kcal/mol. The formation of an extra cross-link affects neither the exchange rate nor the activation enthalpy of category III hydrogens. However, amide hydrogens of residues 34-39 in the vicinity of the hinge are exceptions. They are easily exchanged in the intact lysozyme but their exchange rates are drastically retarded by cross-linking. In the intact lysozyme, structural fluctuations mediating the exchange of category IV hydrogens are highly cooperative with a large activation enthalpy. These large-scale structural fluctuations are the global unfolding of the overall structure and also concerted motions within a domain. Especially near 38 degrees C, it was found that the dominant fluctuation occurring in the alpha-domain is different from that in the beta-domain. However, these concerted motions are strongly quenched by the formation of the cross-link because of the cooperativity of such a large-scale fluctuation. The stabilization of a localized area of protein by cross-linking results in the great suppression of large-scale and concerted motions. The exchange rates of category IV hydrogens are extremely retarded in the cross-linked lysozyme, so that they are exchanged through the so-called penetration mechanism characterized by a low activation enthalpy. These experimental results are discussed with regard to the contribution of cross-linking to the stabilization of the folded structure of protein.
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] 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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11-18-2010 09:15 PM
[NMR paper] A two-dimensional NMR study of exchange behavior of amide hydrogens in a lysozyme der
A two-dimensional NMR study of exchange behavior of amide hydrogens in a lysozyme derivative with an extra cross-link between Glu35 and Trp108--quenching of cooperative fluctuations and effects on the protein stability.
http://www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--www3.interscience.wiley.com-aboutus-images-wiley_interscience_pubmed_logo_120x27.gif Related Articles A two-dimensional NMR study of exchange behavior of amide hydrogens in a lysozyme derivative with an extra cross-link between Glu35 and Trp108--quenching of cooperative fluctuations and effects on the protein...
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08-22-2010 03:31 PM
[NMR paper] Backbone dynamics, amide hydrogen exchange, and resonance assignments of the DNA meth
Backbone dynamics, amide hydrogen exchange, and resonance assignments of the DNA methylphosphotriester repair domain of Escherichia coli Ada using NMR.
http://www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--pubs.acs.org-images-acspubs.jpg Related Articles Backbone dynamics, amide hydrogen exchange, and resonance assignments of the DNA methylphosphotriester repair domain of Escherichia coli Ada using NMR.
Biochemistry. 1996 Jul 23;35(29):9335-48
Authors: Habazettl J, Myers LC, Yuan F, Verdine GL, Wagner G
The 10kDa amino-terminal fragment of...
[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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[NMR paper] The polyelectrolyte behavior of actin filaments: a 25Mg NMR study.
The polyelectrolyte behavior of actin filaments: a 25Mg NMR study.
http://www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--pubs.acs.org-images-acspubs.jpg Related Articles The polyelectrolyte behavior of actin filaments: a 25Mg NMR study.
Biochemistry. 1999 Jun 1;38(22):7219-26
Authors: Xian W, Tang JX, Janmey PA, Braunlin WH
Under physiological conditions, filamentous actin (F-actin) is a polyanionic protein filament. Key features of the behavior of F-actin are shared with other well-characterized polyelectrolytes, in particular, duplex DNA....
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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...