Interaction of peptides with binary phospholipid membranes: application of fluorescence methodologies

The application of fluorescence methodologies to obtain information about the extent, dynamics and topology of peptide interaction with binary phospholipid (mainly zwitterionic/anionic) mixtures is reviewed. First, general approaches based on peptide (tryptophan residues) fluorescence properties that give information about its partition, location and dynamics will be presented. Then, methodologies based on membrane probes fluorescence that report the influence of peptide binding and/or incorporation on the lateral organization (phase separation) of membrane phospholipids will be described. Specific examples taken from the literature that illustrate both situations are presented as well as formalisms for data analysis. It is shown that steady-state and time-resolved fluorescence data (particularly important in the case of fluorescence resonance energy transfer studies) give complementary information, allowing a molecular picture of peptide interaction with biphasic systems to be drawn.