Transverse 1H cross relaxation in 1H-15N correlated 1H CPMG experiments.
Transverse 1H cross relaxation was observed in Carr-Purcell-Meiboom-Gill (CPMG) experiments by recording 15N-1H correlated spectra of amides in HIV protease that was perdeuterated at nonexchangeable sites. Perdeuteration suppresses 1H-1H J coupling and improves spectral resolution and sensitivity. Measurements of cross-peak intensities, arising from cross relaxation, were made as a function of (i) Deltaf, the frequency difference between the spins, and (ii) tauCPMG, one-half of the duration between CPMG pi pulses. Cross peaks were observed when tauCPMG was less than 1/(2Deltaf), in agreement with theoretical calculations.
Molecular Structural Biology Unit, National Institute of Dental and Craniofacial Research, Bethesda, Maryland, 20892-4326, USA.
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R
Ishima
J M
JM
Louis
D A
DA
Torchia
D000577:Amides / Q000032:analysis*; D001381:Azepines; D001665:Binding Sites; D016333:HIV Protease / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D015394:Molecular Structure; D009587:Nitrogen Isotopes / Q000032:analysis; D011522:Protons; D013113:Spin Labels; D014508:Urea / Q000031:analogs & derivatives / Q000737:chemistry
D000577:Amides; D001381:Azepines; D009587:Nitrogen Isotopes; D011522:Protons; D013113:Spin Labels; D014508:Urea; D016333:HIV Protease; C085816:DMP 323