Open Access12‐(9‐Anthroyl)stearic Acid, a Fluorescent Probe for the Ubiquinone Region of the Mitochondrial Membrane
Author(s) -
CHANCE Britton,
ERECINSKA Maria,
RADDA George K.
Publication year - 1975
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1975.tb04165.x
Subject(s) - fluorescence , membrane , stearic acid , chemistry , inner mitochondrial membrane , biophysics , substrate (aquarium) , quenching (fluorescence) , mitochondrion , electron transport chain , membrane fluidity , photochemistry , analytical chemistry (journal) , biochemistry , chromatography , biology , organic chemistry , ecology , physics , quantum mechanics
1 12‐(9‐Anthroyl)stearic acid can be incorporated into mitochondrial membranes. 2 The fluorescence properties of the membrane‐bound probe are different from those of the free molecule. 3 The intensity of emission and fluorescence life‐time of the probe is enhanced when, in the presence of substrate, the electron‐transport chain is reduced. 4 This change in intensity has been demonstrated to be a result of collisional quenching by oxidised ubiquinone in the oxidised membrane but not when the respiratory chain is in the reduced state. 5 In pulsing anaerobic mitochondria with oxygen the rate of the fluorescence change is found to be slower than the rate of ubiquinone oxidation, suggesting that the probe detects a structural transition in the mitochondrial inner membrane. 6 This transition results in a constraint on ubiquinone motion in the reduced system. Model experiments, using lipid dispersions, have been carried out to test some of the interpretations.