Sensitivity-optimized experiment for the measurement of residual dipolar couplings between amide protons.
High signal to noise is a necessity for the quantification of NMR spectral parameters to be translated into accurate and precise restraints on protein structure and dynamics. An important source of long-range structural information is obtained from (1)H-(1)H residual dipolar couplings (RDCs) measured for weakly aligned molecules. For sensitivity reasons, such measurements are generally performed on highly deuterated protein samples. Here we show that high sensitivity is also obtained for protonated protein samples if the pulse schemes are optimized in terms of longitudinal relaxation efficiency and J-mismatch compensated coherence transfer. The new sensitivity-optimized quantitative J-correlation experiment yields important signal gains reaching factors of 1.5 to 8 for individual correlation peaks when compared to previously proposed pulse schemes.
Schanda
Paul
P
Institut de Biologie Structurale - Jean-Pierre Ebel, UMR5075 CNRS-CEA-UJF, 41, rue Jules Horowitz, 38027, Grenoble Cedex 1, France.
Lescop
Ewen
E
Falge
Mirjam
M
Sounier
Rémy
R
Boisbouvier
Jérôme
J
Brutscher
Bernhard
B
D000577:Amides / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D011522:Protons; D015203:Reproducibility of Results
D000577:Amides; D011522:Protons