title: Determining α-helical and β-sheet secondary structures via pulsed electron spin resonance spectroscopy.
abstract: A new method has been developed to determine α-helical and β-sheet secondary structural components of aqueous and membrane-bound proteins using pulsed electron paramagnetic resonance (EPR) spectroscopy. The three-pulse electron spin echo envelope modulation (ESEEM) technique was used to detect weakly coupled (2)H-labeled nuclei on side chains in the proximity of a strategically placed nitroxide spin-label up to 8 Å away. Changes in the ESEEM spectra for different samples correlate directly to periodic structural differences between α-helical and β-sheet motifs. These distinct trends were demonstrated with α-helical (M2δ subunit of the acetylcholine receptor) and β-sheet (ubiquitin) peptides in biologically relevant sample environments.
authors.affiliation: Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, USA.
authors.forename: Andy
authors.initials: A
authors.lastname: Zhou
authors.forename: Shadi
authors.initials: S
authors.lastname: Abu-Baker
authors.forename: Indra D
authors.initials: ID
authors.lastname: Sahu
authors.forename: Lishan
authors.initials: L
authors.lastname: Liu
authors.forename: Robert M
authors.initials: RM
authors.lastname: McCarrick
authors.forename: Carole
authors.initials: C
authors.lastname: Dabney-Smith
authors.forename: Gary A
authors.initials: GA
authors.lastname: Lorigan
mesh_terms: D004578:Electron Spin Resonance Spectroscopy / Q000379:methods*; D056004:Molecular Dynamics Simulation; D017433:Protein Structure, Secondary; D011506:Proteins / Q000737:chemistry*; D013113:Spin Labels
chemical_list: D011506:Proteins; D013113:Spin Labels