Abstract 15N relaxation rates of amide moieties provide insight both into global as well as local backbone dynamics of peptides and proteins. As the differences in the relaxation rates in general are small, their accurate determination is of prime importance. One potential source of error is fast amide exchange. It is well known that in its presence the effects of saturation transfer and H/D exchange may result in erroneous apparent relaxation rates R 1 and R 2. Here, the extent of these errors is rigorously examined. Theoretical considerations reveal that even when saturation effects are absent, H/D exchange will easily result in significant deviations from the true values. In particular overestimations of up to 10 % in R 1 and up to 5 % in R 2 are observed. An alternative scheme for fitting the relaxation data to the corresponding exponentials is presented that in the best cases not only delivers more accurate relaxation rates but also allows extracting estimates for the exchange rates. The theoretical computations were tested and verified for the case of ubiquitin.
Content Type Journal Article
Category Article
Pages 1-12
DOI 10.1007/s10858-012-9682-x
Authors
Simon Jurt, Institute of Organic Chemistry, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
Oliver Zerbe, Institute of Organic Chemistry, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
Mathematical treatment of adiabatic fast passage pulses for the computation of nuclear spin relaxation rates in proteins with conformational exchange
Mathematical treatment of adiabatic fast passage pulses for the computation of nuclear spin relaxation rates in proteins with conformational exchange
Abstract Although originally designed for broadband inversion and decoupling in NMR spectroscopy, recent methodological developments have introduced adiabatic fast passage (AFP) pulses into the field of protein dynamics. AFP pulses employ a frequency sweep, and have not only superior inversion properties with respect to offset effects, but they are also easily implemented into a pulse sequence. As magnetization is dragged from the +z to...
How uniform is the peptide plane geometry? A high-accuracy NMR study of dipolar Cαâ??Câ?²/HNâ??N cross-correlated relaxation
How uniform is the peptide plane geometry? A high-accuracy NMR study of dipolar Cαâ??Câ?²/HNâ??N cross-correlated relaxation
Abstract Highly precise and accurate measurements of very small NMR cross-correlated relaxation rates, namely those between protein HiNâ??Ni and Ciâ??1αâ??Ciâ??1â?² dipoles, are demonstrated with an error of 0.03 sâ??1 for GB3. Because the projection angles between the two dipole vectors are very close to the magic angle the rates range only from â??0.2 to +0.2 sâ??1. Small changes of the average vector orientations have a dramatic impact on the relative values....
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How uniform is the peptide plane geometry? A high-accuracy NMR study of dipolar C(?)-C'/H (N)-N cross-correlated relaxation.
How uniform is the peptide plane geometry? A high-accuracy NMR study of dipolar C(?)-C'/H (N)-N cross-correlated relaxation.
How uniform is the peptide plane geometry? A high-accuracy NMR study of dipolar C(?)-C'/H (N)-N cross-correlated relaxation.
J Biomol NMR. 2011 Jun 3;
Authors: Vögeli B
Highly precise and accurate measurements of very small NMR cross-correlated relaxation rates, namely those between protein H (i) (N) -N(i) and C (i-1) (?) -C(i-1)' dipoles, are demonstrated with an error of 0.03*s(-1) for GB3. Because the projection angles...
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[NMR paper] Influence of internal dynamics on accuracy of protein NMR structures: derivation of r
Influence of internal dynamics on accuracy of protein NMR structures: derivation of realistic model distance data from a long molecular dynamics trajectory.
Related Articles Influence of internal dynamics on accuracy of protein NMR structures: derivation of realistic model distance data from a long molecular dynamics trajectory.
J Mol Biol. 1999 Jan 15;285(2):727-40
Authors: Schneider TR, Brünger AT, Nilges M
In order to study the effect of internal dynamics on the accuracy of NMR structures in detail, we generated NOE distance data from a...
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11-18-2010 07:05 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] 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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15N SOFAST-HMQC to study fast H-D exchange
Very Fast Two-Dimensional NMR Spectroscopy for Real-Time Investigation of Dynamic Events in Proteins on the Time Scale of Seconds
Paul Schanda and Bernhard Brutscher
J. Am. Chem. Soc.; 2005; 127(22) pp 8014 - 8015
http://pubs.acs.org/isubscribe/journals/jacsat/127/i22/figures/ja051306en00001.gif
Abstract:
We demonstrate for different protein samples that 2D 1H-15N correlation NMR spectra can be recorded in a few seconds of acquisition time using a new band-selective optimized flip-angle short-transient heteronuclear multiple quantum coherence experiment. This has enabled us to...
A study on the influence of fast amide exchange on the accuracy of 15N relaxation rate constants
Linear Mode
