title: Rotational diffusion of membrane proteins in aligned phospholipid bilayers by solid-state NMR spectroscopy.
abstract: Solid-state NMR experiments on mechanically aligned bilayer and magnetically aligned bicelle samples demonstrate that membrane proteins undergo rapid rotational diffusion about the normal in phospholipid bilayers. Narrow single-line resonances are observed from 15N labeled sites in the trans-membrane helix of the channel-forming domain of the protein Vpu from HIV-1 in phospholipid bilayers with their normals at angles of 0 degrees, 20 degrees, 40 degrees, and 90 degrees, and bicelles with their normals at angles of 0 degrees and 90 degrees with respect to the direction of the applied magnetic field. This could only occur if the entire polypeptide undergoes rotational diffusion about the bilayer normal. Comparisons between experimental and simulated spectra are consistent with a rotational diffusion coefficient (DR) of approximately 10(5)s-1.
authors.affiliation: Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0307, USA.
authors.forename: Sang Ho
authors.initials: SH
authors.lastname: Park
authors.forename: Anthony A
authors.initials: AA
authors.lastname: Mrse
authors.forename: Alexander A
authors.initials: AA
authors.lastname: Nevzorov
authors.forename: Anna A
authors.initials: AA
authors.lastname: De Angelis
authors.forename: Stanley J
authors.initials: SJ
authors.lastname: Opella
mesh_terms: D004058:Diffusion; D008051:Lipid Bilayers / Q000737:chemistry*; D009587:Nitrogen Isotopes; D019906:Nuclear Magnetic Resonance, Biomolecular / Q000379:methods*; D010743:Phospholipids / Q000737:chemistry*
chemical_list: D008051:Lipid Bilayers; D009587:Nitrogen Isotopes; D010743:Phospholipids