1. Modification of the Elastic Constants of a Peptide-Decorated Lamellar Phase
- Author
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Marcel Waks, John Kauffman, Wladimir Urbach, Nicolas Tsapis, Alain Chaffotte, John Everett, Peter Kahn, Dror E. Warschawski, R. Ober, Laboratoire de Physique de la Matière Condensée (LPMC), Collège de France (CdF (institution))-Centre National de la Recherche Scientifique (CNRS), Biochimie cellulaire, Institut Pasteur [Paris] (IP)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de biologie physico-chimique des protéines membranaires (LBPC-PM (UMR_7099)), Institut de biologie physico-chimique (IBPC (FR_550)), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Rutgers University System (Rutgers), Laboratoire d'Imagerie Paramétrique (LIP), Université Pierre et Marie Curie - Paris 6 (UPMC)-IFR58-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique Statistique de l'ENS (LPS), Fédération de recherche du Département de physique de l'Ecole Normale Supérieure - ENS Paris (FRDPENS), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), N.T. was supported by a 'Société de Secours des Amis des Sciences' fellowship. P.K. acknowledges the support of the New Jersey Agriculture Experiment Station (Paper D-01405-1-01)., Université Paris Diderot - Paris 7 (UPD7)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Fédération de recherche du Département de physique de l'Ecole Normale Supérieure - ENS Paris (FRDPENS), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Institut Pasteur [Paris]-Centre National de la Recherche Scientifique (CNRS), and Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Materials science ,Surfactants ,[SDV]Life Sciences [q-bio] ,Peptide ,02 engineering and technology ,Decane ,Peptides and proteins ,01 natural sciences ,Stiffness ,chemistry.chemical_compound ,Lamellar phase ,0103 physical sciences ,Electrochemistry ,[CHIM]Chemical Sciences ,General Materials Science ,Vesicles ,010306 general physics ,Spectroscopy ,chemistry.chemical_classification ,Bilayer ,Vesicle ,Surfaces and Interfaces ,Lipid bilayer mechanics ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Crystallography ,chemistry ,[SDE]Environmental Sciences ,0210 nano-technology ,Thickness - Abstract
International audience; We have investigated the effect of the insertion of a triblock peptide (hydrophobic−hydrophilic−hydrophobic) in a nonionic lamellar phase composed of C12E4, decane, and water, stabilized by bilayer thermal fluctuations. Circular dichroism shows the peptide to be unordered in water, whereas its hydrophilic part is rigid and organized in an α-helix in the presence of surfactant bilayers. Surface tension measurements prove that the peptide is located at the hydrophobic−hydrophilic interface. Together with spectrofluorometry, these experiments suggest that the peptide lies on the bilayer surface. The Caillé parameter, η, of the lamellar phase, obtained by SAXS experiments, decreases with peptide concentration. This decrease has been interpreted as an increase of the bilayer effective thickness induced by the peptide and is well fitted by a recent model. The bilayer bending rigidity κ increases linearly with peptide concentration, up to two times the rigidity of a bare bilayer with mole ratio of peptide to surfactant as low as 5.2 × 10-4. The smectic compressibility modulus, B̄, decreases, implying that the peptide presence softens interactions between bilayers.
- Published
- 2002