title: Dipolar waves map the structure and topology of helices in membrane proteins.
abstract: Dipolar waves describe the structure and topology of helices in membrane proteins. The fit of sinusoids with the 3.6 residues per turn period of ideal alpha-helices to experimental measurements of dipolar couplings as a function of residue number makes it possible to simultaneously identify the residues in the helices, detect kinks or curvature in the helices, and determine the absolute rotations and orientations of helices in completely aligned bilayer samples and relative rotations and orientations of helices in a common molecular frame in weakly aligned micelle samples. Since as much as 80% of the structured residues in a membrane protein are in helices, the analysis of dipolar waves provides a significant step toward structure determination of helical membrane proteins by NMR spectroscopy.
authors.affiliation: Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive La Jolla, California 92093, USA.
authors.forename: Michael F
authors.initials: MF
authors.lastname: Mesleh
authors.forename: Sangwon
authors.initials: S
authors.lastname: Lee
authors.forename: Gianluigi
authors.initials: G
authors.lastname: Veglia
authors.forename: David S
authors.initials: DS
authors.lastname: Thiriot
authors.forename: Francesca M
authors.initials: FM
authors.lastname: Marassi
authors.forename: Stanley J
authors.initials: SJ
authors.lastname: Opella
mesh_terms: D036022:Capsid Proteins / Q000737:chemistry; D008565:Membrane Proteins / Q000737:chemistry*; D008958:Models, Molecular; D019906:Nuclear Magnetic Resonance, Biomolecular / Q000379:methods*; D017433:Protein Structure, Secondary; D043585:Receptor, Muscarinic M2; D011976:Receptors, Muscarinic / Q000737:chemistry
chemical_list: D036022:Capsid Proteins; D008565:Membrane Proteins; D043585:Receptor, Muscarinic M2; D011976:Receptors, Muscarinic