The structure of polyunsaturated lipid bilayers important for rhodopsin function: a neutron diffraction study.
The structure of oriented 1-stearoyl-2-docosahexaenoyl-sn-glycero-3-phosphocholine bilayers with perdeuterated stearoyl- or docosahexaenoyl hydrocarbon chains was investigated by neutron diffraction. Experiments were conducted at two different relative humidities, 66 and 86%. At both humidities we observed that the polyunsaturated docosahexaenoyl chain has a preference to reside near the lipid water interface. That leaves voids in the bilayer center that are occupied by saturated stearoyl chain segments. This uneven distribution of saturated- and polyunsaturated chain densities is likely to result in membrane elastic stress that modulates function of integral receptor proteins like rhodopsin.
Mihailescu
Mihaela
M
Gawrisch
Klaus
K
D001703:Biophysics / Q000379:methods*; D004281:Docosahexaenoic Acids / Q000737:chemistry; D006838:Hydrocarbons / Q000737:chemistry; D008051:Lipid Bilayers / Q000737:chemistry*; D008055:Lipids / Q000737:chemistry; D008958:Models, Molecular; D033363:Neutron Diffraction; D009502:Neutrons; D016011:Normal Distribution; D010713:Phosphatidylcholines / Q000737:chemistry; D011522:Protons; D012243:Rhodopsin / Q000737:chemistry*; D012542:Scattering, Radiation; D014867:Water / Q000737:chemistry
D006838:Hydrocarbons; D008051:Lipid Bilayers; D008055:Lipids; D010713:Phosphatidylcholines; D011522:Protons; D014867:Water; D004281:Docosahexaenoic Acids; D012243:Rhodopsin