Revertants of nonfunctional cytochrome b mutants were isolated and characterized to determine how specific deleterious mutations in cytochrome b can be suppressed by secondary mutations not restoring a wild type protein. It was recently shown that the cytochrome b function can be recovered following various pseudo-wild type reversions at the level of the original site mutation or adjacent posit...

Cytochrome P-450 and cytochrome b(5) at levels of approximately 0.10 and 0.60 nanomole per milligram of microsomal protein were detected by spectral measurements in microsomes prepared from endosperm tissue of immature Marah macrocarpus seeds. TPNH-cytochrome c reductase, DPNH-cytochrome c reductase, andDPNH-cytochrome b(5) reductase activities were also present in these microsomes at levels of...

The antibiotic stigmatellin was purified from the gliding bacterium Stigmatella aurantiaca [1] and its inhibition of the mitochondrial cytochrome bcl-com plex was characterized in detail [2—4]. Stigmatellin was found to affect the mitochondrial cytochrome bc7-complex at the ubiquinol oxidation site (Q nsite), shifting the a-peak of cytochrome b to the red and raising the redox potential of the ...

This review is focused on the mechanism of ubiquinol oxidation by the cytochrome bc1 complex (bc1). This integral membrane complex serves as a "hub" in the vast majority of electron transfer chains. The bc1 oxidizes a ubiquinol molecule to ubiquinone by a unique "bifurcated" reaction where the two released electrons go to different acceptors: one is accepted by the mobile redox active domain of...

Persian gazelle, Gazella subgutturosa, exists throughout arid and semiarid regions of Iran and has a key role in these frail ecosystems. Habitat degradation and population decline has placed it on the list of vulnerable species in 2008. The phylogenetic relationships of three Persian gazelle populations in the central part of Iran (i.e. Ghamishlou National Park and Wildlife Refuge, Mouteh Wildl...

Chronic granulomatous disease (CGD) is a group of inherited disorders in which phagocytic cells fail to generate antimicrobial oxidants. The various forms of CGD can be classified in terms of the mode of inheritance (either X-linked or autosomal recessive), and whether the neutrophils display the absorbance spectrum of a unique b-type cytochrome important for the function of the respiratory bur...

A procedure permitting the isolation of large amounts of cytochrome b-559 from chloroplasts of barley is described. The isolated cytochrome b-559 has an apparent molecular weight of 120,000. The protein equivalent weight per mole of heme is 30,000. Depending on the electrophoretic conditions used, this molecule can be dissociated into components with apparent molecular weights of 31,000, 30,000...

Erythrocyte NADH-cytochrome b(5) reductase reduces methaemoglobin to functional haemoglobin. In order to examine the function of the enzyme, the structure of NADH-cytochrome b(5) reductase from human erythrocytes has been determined and refined by X-ray crystallography. At 1.75 A resolution, the root-mean-square deviations (r.m.s.d.) from standard bond lengths and angles are 0.006 A and 1.03 de...

Martes species represent a typical example of rapid evolutionary radiation and a recent speciation event. To identify regions of the genome that experienced adaptive evolution, which might provide clues to their functional importance and may be informative about the features that make each species unique, we sought evidence of molecular adaptation in the mitochondrial DNA (mtDNA) cytochrome b g...

Barilius bendelisis is an important food fish and a demanding ornamental species in India. Despite its great economic importance, several wild populations have been suffering drastic reduction. The genetic variability within population is extremely useful for gathering information on individual’s identity, breeding patterns, degree of relatedness and disturbance of genetic variation among them....