A single-quantum methyl 13C-relaxation dispersion experiment with improved sensitivity.
A pulse sequence is described for recording single-quantum (13)C-methyl relaxation dispersion profiles of (13)C-selectively labeled methyl groups in proteins that offers significant improvements in sensitivity relative to existing approaches where initial magnetization derives from (13)C polarization. Sensitivity gains in the new experiment are achieved by making use of polarization from (1)H spins and (1)H --> (13)C --> (1)H type magnetization transfers. Its utility has been established by applications involving three different protein systems ranging in molecular weight from 8 to 28 kDa, produced using a number of different selective labeling approaches. In all cases exchange parameters from both (13)C-->(1)H and (1)H --> (13)C --> (1)H classes of experiment are in good agreement, with gains in sensitivity of between 1.7 and 4-fold realized using the new scheme.
Lundström
Patrik
P
Department of Medical Genetics, The University of Toronto, Toronto, ON, Canada, M5S 1A8.
Vallurupalli
Pramodh
P
Religa
Tomasz L
TL
Dahlquist
Frederick W
FW
Kay
Lewis E
LE
D002247:Carbon Isotopes / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D011506:Proteins / Q000737:chemistry*; D015203:Reproducibility of Results
D002247:Carbon Isotopes; D011506:Proteins