title: Aminosilane/oleic acid vesicles as model membranes of protocells.
abstract: Oleic acid vesicles represent good models of membrane protocells that could have existed in prebiotic times. Here, we report the formation, growth polymorphism, and dynamics of oleic acid spherical vesicles (1-10 μm), stable elongated vesicles (>50 μm length; 1-3 μm diameter), and chains of vesicles (pearl necklaces, >50 μm length; 1-3 μm diameter) in the presence of aminopropyl triethoxysilane and guanidine hydrochloride. These vesicles exhibit a remarkable behavior with temperature: spherical vesicles only are observed when keeping the sample at 4 °C for 2 h, and self-aggregated spherical vesicles occur upon freezing/unfreezing (-20/20 °C) samples. Rather homogeneous elongated vesicles are reformed upon heating samples at 80 °C. The phenomenon is reversible through cycles of freezing/heating or cooling/heating of the same sample. Deuterium NMR evidences a chain packing rigidity similar to that of phospholipid bilayers in cellular biomembranes. We expect these bilayered vesicles to be surrounded by a layer of aminosilane oligomers, offering a variant model for membrane protocells.
authors.affiliation: UMR 1332, biologie et pathologie du fruit, INRA, centre de Bordeaux, 33883 Villenave d'Ornon, France.
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Douliez
authors.forename: Vanessa
authors.initials: V
authors.lastname: Zhendre
authors.forename: Axelle
authors.initials: A
authors.lastname: Grélard
authors.forename: Erick J
authors.initials: EJ
authors.lastname: Dufourc
mesh_terms: D000588:Amines / Q000737:chemistry*; D006108:Graphite / Q000737:chemistry*; D008958:Models, Molecular; D056004:Molecular Dynamics Simulation; D019301:Oleic Acid / Q000737:chemistry*; D012821:Silanes / Q000737:chemistry*; D022161:Transport Vesicles / Q000737:chemistry*
chemical_list: D000588:Amines; D012821:Silanes; D019301:Oleic Acid; D006108:Graphite