title: Interaction of cytochrome c with 1-palmitoyl-2-azelaoyl-sn-glycero-3-phosphocholine: evidence for acyl chain reversal.
abstract: The conformational dynamics of the oxidatively modified phospholipid 1-palmitoyl-2-azelaoyl-sn-glycero-3-phosphocholine (PazePC) were assessed by observing by fluorescence energy transfer the association of the water-soluble cationic protein cytochrome c with micelles composed of this lipid. In keeping with reversal of the azelaoyl chain so as to expose its carboxyl function on the micelle surface, cytochrome c bound avidly to the micelles. In contrast, the aldehyde group bearing 1-palmitoyl-2-(9'-oxo-nonanoyl)-sn-glycero-3-phosphocholine (PoxnoPC) interacted only weakly. While the physiological significance of the above interaction is uncertain, our results demonstrate that oxidative damage alters the physical properties of lipid bilayers, involving enrichment of the polar moieties of oxidatively modified lipid chains within the membrane surface.
authors.affiliation: Helsinki Biophysics and Biomembrane Group, Institute of Biomedicine/Medical Biochemistry (Haartmaninkatu 8), University of Helsinki, Finland.
authors.forename: Juha-Pekka
authors.initials: JP
authors.lastname: Mattila
authors.forename: Karen
authors.initials: K
authors.lastname: Sabatini
authors.forename: Paavo K J
authors.initials: PK
authors.lastname: Kinnunen
mesh_terms: D000818:Animals; D045304:Cytochromes c / Q000737:chemistry* / Q000378:metabolism; D006736:Horses; D015394:Molecular Structure; D010767:Phosphorylcholine / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism; D011485:Protein Binding; D017186:Titrimetry
chemical_list: C528536:1-palmitoyl-2-azelaoyl-sn-glycero-3-phosphocholine; D010767:Phosphorylcholine; D045304:Cytochromes c