[Changes in the structural state of boundary lipids in bacterial membrane under effect of the membranotropic antibiotic gramicidin S].
Using data from measurements of excimerization at different wave-lengths of fluorescence excitation of the fluorescent probe pyrene in isolated M. lysodeikticus membranes and using the phenomenon of energy transfer in the protein tryptophanyl-pyrene system, a method for monitoring the probe population localized in the immediate proximity to protein structures, has been developed. This method allows to detect the existence within the physiological temperature range of a specific lipid population or a boundary lipid vicinal to the membrane proteins. The changes in this region under membrane treatment with the cyclodecapeptide antibiotic gramicidin S were studied. Incubation of membranes with the antibiotic increases the efficiency of quenching of membrane protein fluorescence by the quenchers localized in the membrane phase, i.e. 2-(14-carboxytetradecyl)-2-ethyl-4,4-dimethyl-3-oxasolidinyloxyl, cetylpyridinium chloride and pyrene, and changes the protein chromophore accessibility for J-. The lateral mobility of pyrene during gramicidin S adsorption on the lipid and protein-lipid membranes is decreased. The results obtained are interpreted in favour of partial disturbance in the interaction of the boundary lipid and membrane proteins under effects of gramicidin S.
D002462:Cell Membrane / Q000187:drug effects / Q000648:ultrastructure; D006096:Gramicidin / Q000494:pharmacology*; D007700:Kinetics; D008563:Membrane Lipids / Q000378:metabolism*; D008837:Micrococcus / Q000648:ultrastructure*; D013050:Spectrometry, Fluorescence; D013696:Temperature
D008563:Membrane Lipids; D006096:Gramicidin
Izmenenie strukturnogo sostoianiia pogranichnykh lipidov v bakterial'noĭ membrane pri deĭstvii membranotropnogo antibiotika gramitsidina S.