Not Only Oxidation of Cardiolipin Affects the Affinity of Cytochrome c for Lipid Bilayers

摘要: Fluorescence quenching of lipid-bound pyrene was used to assess the binding cytochrome c (cyt c) liposomes that mimic inner mitochondrial membrane (IMM) POPC/DOPE/TOCL, with conditions it did or not contain oxidized phosphatidylcholine molecules, i.e., 1-O-hexadecyl-2-azelaoyl-sn-glycero-3-phosphocholine (PazePC), a mixture two hydroperoxide isomers derived from POPC (POPCOX). The isotherms reveal dissociation constants, KD1 and KD2, representing, respectively, low- high-affinity states membrane. These constants probably are due lipid reorganization promoted by cyt c, as observed in giant unilamellar vesicles fluorescent cardiolipin (CL). presence PazePC, which has nonreactive carboxylic group, increased KD2 values 1.2- 4.5-fold, respectively. POPCOX reactive peroxide decreased value 1.5-fold, 10-fold, significantly reduced...