Leung 1975 J Biol Chem
| Leung KH, Hinkle PC (1975) Reconstitution of ion transport and respiratory control in vesicles formed from reduced coenzyme Q-cytochrome c reductase and phospholipids. J Biol Chem 250: 8467-8471. |
Leung KH, Hinkle PC (1975) J Biol Chem
Abstract: Reduced coenzyme Q-cytochrome c reductase from bovine heart mitochondria (complex III) was incorporated into phospholipid vesicles by the cholate dialysis procedure. Soybean phospholipids or mixtures of purified phosphatidylcholine, phosphatidylethanolamine, and cardiolipin could be used. Oxidation of reduced coenzyme Q2 by the reconstituted vesicles with cytochrome c as oxidant showed the following energy-coupling phenomena. 1. Protons were translocated outward with a coupling ratio, H+/2e, of 1.9 +/- 0.2. Measurements with mitochondria under similar conditions showed an H+/2e ratio of 1.8. Proton translocation was not seen in the presence of uncoupling agents and was in addition to the net acidification of the medium from the over-all oxidation reaction. 2. Potassium ions were taken up by the reconstituted vesicles in the presence of valinomycin in a reaction coupled to electron transfer. The coupling ratio for K+ uptake, K+/2e, was 2.0 in the vesicles and approximately 1.5 in mitochondria. 3. The rate of oxidation of reduced coenzyme Q2 by the reconstituted vesicles was stimulated up to 10-fold by uncouplers or by valinomycin plus nigericin and K+ ions. Addition of valinomycin alone in a K+ medium caused a transient stimulation of electron transfer. The results indicate that energy coupling can be observed with isolated reduced coenzyme Q-cytochrome c reductase if the enzyme complex is properly incorporated into a phospholipid vesicle. • Keywords: ion transport, respiratory control, coenzyme Q-cytochrome c reductase, phospholipids, vesicles
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Organism: Other Mammal"Other Mammal" is not in the list (Human, Pig, Mouse, Rat, Guinea pig, Bovines, Horse, Dog, Rabbit, Cat, ...) of allowed values for the "Mammal and model" property.
Tissue;cell: Cardiac muscle"Cardiac muscle" is not in the list (Heart, Skeletal muscle, Nervous system, Liver, Kidney, Lung;gill, Islet cell;pancreas;thymus, Endothelial;epithelial;mesothelial cell, Blood cells, Fat, ...) of allowed values for the "Tissue and cell" property.
Preparation: Isolated Mitochondria"Isolated Mitochondria" is not in the list (Intact organism, Intact organ, Permeabilized cells, Permeabilized tissue, Homogenate, Isolated mitochondria, SMP, Chloroplasts, Enzyme, Oxidase;biochemical oxidation, ...) of allowed values for the "Preparation" property.
Regulation: Respiration; OXPHOS; ETS Capacity"Respiration; OXPHOS; ETS Capacity" is not in the list (Aerobic glycolysis, ADP, ATP, ATP production, AMP, Calcium, Coupling efficiency;uncoupling, Cyt c, Flux control, Inhibitor, ...) of allowed values for the "Respiration and regulation" property.
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