title: Multi-lamellar organization of fully deuterated lipid extracts of yeast membranes.
abstract: Neutron scattering studies on mimetic biomembranes are currently limited by the low availability of deuterated unsaturated lipid species. In the present work, results from the first neutron diffraction experiments on fully deuterated lipid extracts from the yeast Pichia pastoris are presented. The structural features of these fully deuterated lipid stacks are compared with those of their hydrogenous analogues and with other similar synthetic systems. The influence of temperature and humidity on the samples has been investigated by means of small momentum-transfer neutron diffraction. All of the lipid extracts investigated self-assemble into multi-lamellar stacks having different structural periodicities; the stacking distances are affected by temperature and humidity without altering the basic underlying arrangement. At high relative humidity the deuterated and hydrogenous samples are similar in their multi-lamellar arrangement, being characterized by two main periodicities of ∼75 and ∼110 Å reflecting the presence of a large number of polar phospholipid molecules. Larger differences are found at lower relative humidity, where hydrogenous lipids are characterized by a larger single lamellar structure than that observed in the deuterated samples. In both cases the heterogeneity in composition is reflected in a wide structural complexity. The different behaviour upon dehydration can be related to compositional differences in the molecular composition of the two samples, which is attributed to metabolic effects related to the use of perdeuterated growth media.
authors.affiliation: Institut Laue-Langevin, 71 Avenue des Martyrs, 38000 Grenoble, France.
authors.forename: Yuri
authors.initials: Y
authors.lastname: Gerelli
authors.affiliation: Institut Laue-Langevin, 71 Avenue des Martyrs, 38000 Grenoble, France.
authors.forename: Alexis
authors.initials: A
authors.lastname: de Ghellinck
authors.affiliation: Laboratoire de Physiologie Cellulaire and Végétale (LPCV), CNRS (UMR5168)/Université Grenoble Alpes/INRA (USC1359)/CEA Grenoble, Institut de Recherches en Technologies et Sciences pour le Vivant (iRTSV), 17 Rue des Martyrs, 38054 Grenoble CEDEX 9, France.
authors.forename: Juliette
authors.initials: J
authors.lastname: Jouhet
authors.affiliation: Institut Laue-Langevin, 71 Avenue des Martyrs, 38000 Grenoble, France.
authors.forename: Valérie
authors.initials: V
authors.lastname: Laux
authors.affiliation: Institut Laue-Langevin, 71 Avenue des Martyrs, 38000 Grenoble, France.
authors.forename: Michael
authors.initials: M
authors.lastname: Haertlein
authors.affiliation: Institut Laue-Langevin, 71 Avenue des Martyrs, 38000 Grenoble, France.
authors.forename: Giovanna
authors.initials: G
authors.lastname: Fragneto
mesh_terms: D003903:Deuterium / Q000737:chemistry / Q000302:isolation & purification; D006813:Humidity; D008051:Lipid Bilayers / Q000737:chemistry / Q000302:isolation & purification; D008055:Lipids / Q000737:chemistry* / Q000302:isolation & purification; D033363:Neutron Diffraction; D010843:Pichia / Q000737:chemistry*
chemical_list: D008051:Lipid Bilayers; D008055:Lipids; D003903:Deuterium
keywords: full deuteration; lipid extracts; neutron scattering