This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Klymchenko, A. S. Articles by Mély, Y. Search for Related Content PubMed PubMed Citation Articles by Klymchenko, A. S. Articles by Mély, Y.

Bimodal Distribution and Fluorescence Response of Environment-Sensitive Probes in Lipid Bilayers

Andrey S. Klymchenko ^*, Guy Duportail ^*, Alexander P. Demchenko   and Yves Mély ^*

^* Laboratoire de Pharmacologie et Physicochimie, Unité Mixte de Recherche 7034 du Centre National de la Recherche Scientifique, Faculté de Pharmacie, Université Louis Pasteur, Illkirch, France; A. V. Paladin Institute of Biochemistry, Kiev, Ukraine; and The Scientific and Technical Research Council of Turkey, Research Institute for Genetic Engineering and Biotechnology, Gebze-Kocaeli, Turkey

Correspondence: Address reprint requests to Dr. Andrey S. Klymchenko, Laboratoire de Pharmacologie et Physicochimie, UMR 7034 du CNRS, Faculté de Pharmacie, Université Louis Pasteur, BP 24, 67401 Illkirch, France. Tel.: 33-390-24-4115; Fax: 33-390-24-4312; E-mail: aklymchenko{at}aspirine.u-strasbg.fr.

A remarkable heterogeneity is often observed in the spectroscopic properties of environment-sensitive fluorescence probes in phospholipid bilayers. To explain its origin, we provided a detailed investigation of the fluorescence excitation and emission spectra of 4'-dimethylamino-3-hydroxyflavone (probe F) in bilayer vesicles with the variations of fatty acid composition, polar heads, temperature, and cholesterol content. Probe F, due to excited-state intramolecular proton transfer, exhibits two bands in emission that are differently sensitive to intermolecular interactions—thereby allowing us to distinguish universal (dipole-dipole) and specific (H-bonding) interactions within the bilayer. Spectroscopic, quenching, and anisotropy data suggest the presence of two forms of probe F at different locations in the bilayer: an H-bond free form located below sn₁-carbonyls and an H-bonded form located at the polar membrane interface. We provide a quantitative analysis of the distribution of the probe between these two locations as well as the polarity of these locations, and show that both the distribution and the polarity contribute to the probe response. Moreover, analysis of literature data on other environment-sensitive probes (Prodan, Laurdan, Nile Red, NBD lipids, etc.) in lipid bilayers allows us to suggest that the bimodal distribution in the lipid bilayer is probably a general feature of low-polar molecules with polar groups capable of H-bonding interactions.

This article has been cited by other articles:

				G. M'Baye, Y. Mely, G. Duportail, and A. S. Klymchenko Liquid Ordered and Gel Phases of Lipid Bilayers: Fluorescent Probes Reveal Close Fluidity but Different Hydration Biophys. J., August 1, 2008; 95(3): 1217 - 1225. [Abstract] [Full Text] [PDF]

				A. R. Burns, D. J. Frankel, and T. Buranda Local Mobility in Lipid Domains of Supported Bilayers Characterized by Atomic Force Microscopy and Fluorescence Correlation Spectroscopy Biophys. J., August 1, 2005; 89(2): 1081 - 1093. [Abstract] [Full Text] [PDF]

				Y. J. E. Bjorkqvist, T. K. M. Nyholm, J. P. Slotte, and B. Ramstedt Domain Formation and Stability in Complex Lipid Bilayers as Reported by Cholestatrienol Biophys. J., June 1, 2005; 88(6): 4054 - 4063. [Abstract] [Full Text] [PDF]