title: Interresidue carbonyl-carbonyl polarization transfer experiments in uniformly 13C,15N-labeled peptides and proteins.
abstract: In this work, we demonstrate that Homonuclear Rotary Resonance Recoupling (HORROR) can be used to reintroduce carbonyl-carbonyl interresidue dipolar interactions and to achieve efficient polarization transfer between carbonyl atoms in uniformly (13)C,(15)N-labeled peptides and proteins. We show that the HORROR condition is anisotropically broadened and overall shifted to higher radio frequency intensities because of the CSA effects. These effects are analyzed theoretically using Average Hamiltonian Theory. At spinning frequencies used in this study, 22kHz, this broadening is experimentally found to be on the order of a kilohertz at a proton field of 600MHz. To match HORROR condition over all powder orientations, variable amplitude radio frequency (RF) fields are required, and efficient direct transfers on the order of 20-30% can be straightforwardly established. Two- and three-dimensional chemical shift correlation experiments establishing long-range interresidue connectivities (e.g., (N[i]-CO[i-2])) are demonstrated on the model peptide N-acetyl-valine-leucine, and on the third immunoglobulin binding domain of protein G. Possible future developments are discussed.
authors.affiliation: Department of Physics, University of Guelph, 50 Stone Road East, Guelph, Ont, Canada.
authors.forename: Rafal
authors.initials: R
authors.lastname: Janik
authors.forename: Emily
authors.initials: E
authors.lastname: Ritz
authors.forename: Andrew
authors.initials: A
authors.lastname: Gravelle
authors.forename: Lichi
authors.initials: L
authors.lastname: Shi
authors.forename: Xiaohu
authors.initials: X
authors.lastname: Peng
authors.forename: Vladimir
authors.initials: V
authors.lastname: Ladizhansky
mesh_terms: D000465:Algorithms; D016880:Anisotropy; D002247:Carbon Isotopes; D004574:Electromagnetic Fields; D007136:Immunoglobulins / Q000737:chemistry; D009419:Nerve Tissue Proteins / Q000737:chemistry; D009587:Nitrogen Isotopes; D019906:Nuclear Magnetic Resonance, Biomolecular / Q000379:methods*; D010455:Peptides / Q000737:chemistry*; D050050:Protein Carbonylation; D011506:Proteins / Q000737:chemistry*; D011522:Protons; D011971:Receptors, Immunologic
chemical_list: D002247:Carbon Isotopes; C029152:G-substrate; D007136:Immunoglobulins; D009419:Nerve Tissue Proteins; D009587:Nitrogen Isotopes; D010455:Peptides; D011506:Proteins; D011522:Protons; D011971:Receptors, Immunologic