## Abstract Chemical exchange phenomena in NMR spectra reveal protein motions on microsecond to millisecond time scales that are associated with biological functions, including catalysis, ligand binding, allosteric conformational changes and protein folding. This review surveys solution NMR methods
Relaxation compensation in chemical exchange measurements for the quantitation of amide hydrogen exchange in larger proteins
✍ Scribed by Griselda Hernández; David M. LeMaster
- Publisher
- John Wiley and Sons
- Year
- 2003
- Tongue
- English
- Weight
- 151 KB
- Volume
- 41
- Category
- Article
- ISSN
- 0749-1581
- DOI
- 10.1002/mrc.1239
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
The increasingly rapid transverse relaxation of larger macromolecules serves to limit the practical length of various types of mixing periods. When chemical exchange dynamics are used to determine the rates of amide hydrogen exchange with the bulk solvent, the foreshortened mixing period results in lowered sensitivity. Three approaches are examined for increasing the practical length of the mixing period. The transverse relaxation rate of the amide resonances is decreased by perdeuteration of the carbon‐bound hydrogen positions and also by introduction of a TROSY‐based ^15^N‐separated pulse sequence. Reference experiments are proposed which provide accurate compensation for relaxation effects so that exchange rate data can be obtained over the entire mixing period profile. As a result, more than a 100‐fold range of amide exchange rates can be accurately determined for a moderate‐sized protein. Copyright © 2003 John Wiley & Sons, Ltd.
📜 SIMILAR VOLUMES
The potentialities of a 2D proton-detected heteronuclear exchange experiment to assign the nitrogen and amide proton resonances in a uniformly 15 N-enriched macromolecule involved in a complex, starting from the free form assignments, are demonstrated on a protein-DNA complex. This 2D experiment is
An experimental approach for the editing of exchange-relayed NOEs in water-selective NOE experiments is presented. The proposed pulse sequence is based on the application during the NOE mixing time of continuous wave irradiation, which saturates resonances of relaying labile protons in slow chemical
A fundamental problem in Fourier transform NMR spectroscopy is the calculation of observed resonance amplitudes for a repetitively pulsed sample, as first analyzed by Ernst and Anderson in 1966. Applications include determination of spin-lattice relaxation times (T 1 's) by progressive saturation an