[Interaction of spin-labeled saturated and unsaturated fatty acid derivatives with biological membrane lipid and protein components]

Interaction of saturated and unsaturated derivatives of spin-labelled fatty acids (2,2,6,6-tetramethyl-4-palmitoylpiperidil-l-oxyl (I) and synthetized by us 2,2,6,6-tetramethyl-4-oleoylpiperidil-1-oxyl (II) with sarcoplasmic reticulum membranes, retina rod outer segments and erythorocyte ghosts was studied. ESR spectra of the probe I are practically unresolved singlets, whereas ESR spectra of the probe II appear as more of less resolved triplet signals. The difference in ESR spectra of the probes I and II is the result of distribution of the probe I in pure lipid regions of membranes, the probe II being located both in lipid bilayer and hydrophobic areas of proteins.