title: Triple resonance-based ¹³C(α) and ¹³C(β) CEST experiments for studies of ms timescale dynamics in proteins.
abstract: A pair of triple resonance based CEST pulse schemes are presented for measuring ¹³C(α) and ¹³C(β) chemical shifts of sparsely populated and transiently formed conformers that are invisible to traditional NMR experiments. CEST profiles containing dips at resonance positions of ¹³C(α) or ¹³C(β) spins of major (ground) and minor (excited) conformers are obtained in a pseudo 3rd dimension that is generated by quantifying modulations of cross peaks in ¹⁵N, ¹H(N) correlation spectra. An application to the folding reaction of a G48A mutant of the Fyn SH3 domain is presented, illustrating and validating the methodology.
authors.affiliation: Departments of Molecular Genetics, Biochemistry and Chemistry, The University of Toronto, Toronto, ON, M5S 1A8, Canada.
authors.forename: Dong
authors.initials: D
authors.lastname: Long
authors.forename: Ashok
authors.initials: A
authors.lastname: Sekhar
authors.forename: Lewis E
authors.initials: LE
authors.lastname: Kay
mesh_terms: D002247:Carbon Isotopes / Q000737:chemistry*; D056004:Molecular Dynamics Simulation; D019906:Nuclear Magnetic Resonance, Biomolecular / Q000379:methods*; D011487:Protein Conformation; D011506:Proteins / Q000737:chemistry*; D059629:Signal-To-Noise Ratio
chemical_list: D002247:Carbon Isotopes; D011506:Proteins