title: The structure of DHA in phospholipid membranes.
abstract: Early experiments and molecular simulations of PUFA favored a rigid arrangement of double bonds in U-shaped or extended conformations such as angle-iron or helical. Although results of recent solid-state NMR measurements and molecular simulations have confirmed the existence of these structural motifs, they portray an image of DHA (22:6n-3) as a highly flexible molecule with rapid transitions between large numbers of conformers on the time scale from picoseconds to hundreds of nanoseconds. The low barriers to torsional rotation about C-C bonds that link the cis-locked double bonds with the methylene carbons between them are responsible for this unusual flexibility. Both the amplitude and frequency of motion increase toward the terminal methyl group of DHA.
authors.affiliation: Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, Maryland 20852, USA. gawrisch@helix.nih.gov
authors.forename: Klaus
authors.initials: K
authors.lastname: Gawrisch
authors.forename: Nadukkudy V
authors.initials: NV
authors.lastname: Eldho
authors.forename: Laura L
authors.initials: LL
authors.lastname: Holte
mesh_terms: D004281:Docosahexaenoic Acids / Q000737:chemistry* / Q000378:metabolism; D005231:Fatty Acids, Unsaturated / Q000737:chemistry / Q000378:metabolism; D008051:Lipid Bilayers / Q000737:chemistry* / Q000378:metabolism; D008958:Models, Molecular; D008968:Molecular Conformation; D019906:Nuclear Magnetic Resonance, Biomolecular; D010743:Phospholipids / Q000737:chemistry* / Q000378:metabolism; D013816:Thermodynamics
chemical_list: D005231:Fatty Acids, Unsaturated; D008051:Lipid Bilayers; D010743:Phospholipids; D004281:Docosahexaenoic Acids