title: A simple method to measure 13CH2 heteronuclear dipolar cross-correlation spectral densities.
abstract: Here, we report a method to simultaneously determine CH2 cross-correlation spectral densities and T1 relaxation times in the laboratory and rotating frames. To accomplish this, we have employed an indirect approach that is based on measurement of differences in relaxation rates acquired with and without cross-correlation terms. The new method, which can be employed using multidimensional NMR and standard relaxation pulse sequences, is validated experimentally by investigation of a selectively 13C-enriched hexadecapeptide and the uniformly 13C-enriched immunoglobulin-binding domain of streptococcal protein G (GB1). Use of this approach makes determination of CH2 cross-correlation spectral densities in uniformly 13C-enriched proteins now routine and provides novel information concerning their internal motions.
authors.affiliation: Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota Health Science Center, 321 Church Street, Minneapolis, MN 55455, USA.
authors.forename: Djaudat
authors.initials: D
authors.lastname: Idiyatullin
authors.forename: Vladimir A
authors.initials: VA
authors.lastname: Daragan
authors.forename: Kevin H
authors.initials: KH
authors.lastname: Mayo
mesh_terms: D001426:Bacterial Proteins / Q000032:analysis*; D002247:Carbon Isotopes; D006859:Hydrogen / Q000737:chemistry; D019906:Nuclear Magnetic Resonance, Biomolecular / Q000379:methods*; D010455:Peptides / Q000032:analysis*; D012815:Signal Processing, Computer-Assisted
chemical_list: D001426:Bacterial Proteins; D002247:Carbon Isotopes; C034284:IgG Fc-binding protein, Streptococcus; D010455:Peptides; D006859:Hydrogen