The degree of freedom for lateral translational diffusion by cytochrome c oxidase and other integral proteins in the energy-transducing membrane of the mitochondrion was determined by combining the use of an immunoglobulin probe monospecific for the oxidase with thermotropic lipid phase transitions. Lateral mobility of the oxidase was monitored by observing the distribution of the immunoglobuli...

Cytochrome c release from mitochondria induces caspase activation in cytosols; however, it is unclear whether the redox state of cytosolic cytochrome c can regulate caspase activation. By using cytosol isolated from mammalian cells, we find that oxidation of cytochrome c by added cytochrome oxidase stimulates caspase activation, whereas reduction of cytochrome c by added tetramethylphenylenedia...

The aim of the study was to determine the activity of cytochrome c oxidase in mitochondrial fractions of cataractogenic epithelial cells of lenses of 60 patients (34 females and 26 males). According to clinical criteria patients were divided into three groups: group 1--patients with senile cataract, group 2--active smokers with senile cataract, and group 3--diabetic patients with cataract as di...

Liver microsomes contain a mixed function oxidase system capable of metabolizing a broad range of biologically active substances, including drugs, steroids, and environmental chemicals such as polycyclic hydrocarbons. Certain hemoproteins, collectively referred to as cytochrome P-450, function as the terminal oxidase in this system. The fact that this hepatic mixed function oxidase system is se...

A preparation of reconstituted cytochrome oxidase vesicles in which the enzyme is oriented facing inwards (such that it cannot interact with external cytochrome c) is described. No oxidase activity is expressed by these vesicles unless they are disrupted, allowing influx of cytochrome c or exposure of the oxidase-binding site to the external medium. We have exploited this property to follow det...

Porphyromonas gingivalis is an etiologic agent of periodontal disease in humans. The disease is associated with the formation of a mixed oral biofilm which is exposed to oxygen and environmental stress, such as oxidative stress. To investigate possible roles for cytochrome bd oxidase in the growth and persistence of this anaerobic bacterium inside the oral biofilm, mutant strains deficient in c...

Z. Naturforsch. 43c, 438-442 (1988); received December 7, 1987/February 10, 1988 Cu Deficiency, Cytochrome Oxidase, Mitochondria, Pea Plants, Scenedesmus In Scenedesmus about half of N A D H oxidation proceeds via a cyanide-sensitive and the other half via a cyanide-insensitive respiratory pathway. In contrast, respiration is completely cyanide sensitive in pea indicating that the alternative r...

The interactions between redox proteins are transient in nature. Therefore, very few crystal structures are available for the complexes formed between these proteins. Computational docking simulations thus provide a useful alternative method for studying the interactions between electron transfer proteins. In this paper, we have studied the interactions between the aa(3)-type cytochrome c oxida...

Ubiquinol oxidase has been reconstituted from ubiquinol-cytochrome c reductase (Complex III), cytochrome c and cytochrome c oxidase (Complex IV). The steady-state level of reduction of cytochrome c by ubiquinol-2 varies with the molar ratios of the complexes and with the presence of antimycin in a way that can be quantitatively accounted for by a model in which cytochrome c acts as a freely dif...