Effect of a laminin amphiphatic sequence on DPPC ordered bilayers

✍ Scribed by F. Reig; A. Juvé; A. Ortiz; P. Sospedra; M. A. Alsina

• Book ID: 101715449
• Publisher: John Wiley and Sons
• Year: 2005
• Tongue: English
• Weight: 137 KB
• Volume: 20
• Category: Article
• ISSN: 1522-7235
• DOI: 10.1002/bio.851

✦ Synopsis

Abstract

A peptide sequence, stearoyl‐GESIKVAVS(NH~2~), related to a laminin fragment, has been synthesized. Formation of aggregates was controlled by titrating a sodium anilinonaphthalene sulphonate (ANS) solution with peptide and recording fluorescence intensity increases. The results show that this system experiences a sudden increase in fluorescence at peptide concentrations around 2.5 × 10^−4^ mol/L. The interaction of this hydrophobic peptide with DPPC vesicles has been studied using fluorescence techniques. Its influence on the microviscosity of bilayers was determined by studying polarization/temperature dependence for ANS and diphenyl hexatriene (DPH) fluorescent probes. With both markers the presence of peptide promotes a clear increase in anisotropy values. This indicates a rigidifying effect. Leakage studies carried out with liposomes loaded with carboxyfluorescein (CF) indicate a stabilizing effect of the peptide on bilayers, in agreement with results obtained with fluorescent probes. Copyright © 2005 John Wiley & Sons, Ltd.