title: Absorption and fluorescence spectra of polyene antibiotics in the presence of cholesterol.
abstract: The alterations in the absorption and fluorescence spectra observed for the polyene antibiotics filipin and nystatin in the presence of cholesterol are due to an exciton interaction (polyene aggregates) and cannot be attributed to a specific sterol-antibiotic complex. Filipin and nystatin molecules partition into the sterol aggregates, these structures being very efficient to induce exciton interaction; the observed splitting profile indicates that the chromophores are in a stacked arrangement (parallel transition dipoles). For filipin incorporated in lipid bilayers, the sterol is able to induce the same type of aggregate, at variance with nystatin.
authors.affiliation: Centro de Química Física Molecular, Instituto Superior Técnico, Lisboa, Portugal.
authors.forename: M A
authors.initials: MA
authors.lastname: Castanho
authors.forename: A
authors.initials: A
authors.lastname: Coutinho
authors.forename: M J
authors.initials: MJ
authors.lastname: Prieto
mesh_terms: D015060:1,2-Dipalmitoylphosphatidylcholine; D002784:Cholesterol / Q000737:chemistry*; D005372:Filipin / Q000737:chemistry*; D005454:Fluorescence Polarization; D008051:Lipid Bilayers; D008081:Liposomes; D015394:Molecular Structure; D009761:Nystatin / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet
chemical_list: D008051:Lipid Bilayers; D008081:Liposomes; D009761:Nystatin; D015060:1,2-Dipalmitoylphosphatidylcholine; D005372:Filipin; D002784:Cholesterol