Improved TROSY-HNCA experiment with suppression of conformational exchange induced relaxation.
A general method for improving of the sensitivity of the TROSY-type triple resonance experiments in the presence of conformational exchange-induced (CSX) relaxation is proposed based on the use of CPMG-INEPT (Müller et al., J. Am. Chem. Soc., 1995, 117, 11043-11048) during the N-C polarization transfer periods. Significantly improved sensitivity is demonstrated for the majority of cross-peaks in the new [15N,1H]-TROSY-XY-HNCA experiment, measured with partially folded RNase AS-Protein, with negligible loss of sensitivity for resonances unaffected by CSX relaxation. In addition, a comparison of cross-peak amplitudes in [15N,1N]-TROSY-XY-HNCA and conventional [15N,1H]-TROSY-HNCA spectra provides a quick and sensitive estimation of the CSX relaxation contribution.
Pervushin
K
K
Laboratorium für Physikalische Chemie, Eidgenössische Technische Hochschule Hönggerberg, Zürich, Switzerland. kope@phys.chem.ethz.ch
Gallius
V
V
Ritter
C
C
D002247:Carbon Isotopes; D006859:Hydrogen; D009587:Nitrogen Isotopes; D019906:Nuclear Magnetic Resonance, Biomolecular / Q000379:methods*; D011487:Protein Conformation; D011506:Proteins / Q000737:chemistry*; D012259:Ribonuclease, Pancreatic / Q000737:chemistry
D002247:Carbon Isotopes; D009587:Nitrogen Isotopes; D011506:Proteins; D006859:Hydrogen; D012259:Ribonuclease, Pancreatic