Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:1.9.3.1 (cytochrome oxidase)
 8,822 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A fifth cytoplasmic mutation (capr 1) obtained in Podospora anserina is described. In addition to chloramphenicol resistance it confers a strong deficiency in cytochrome aa3 and impairs the germination of ascospores. Genetic analysis shows: 1) strict maternal inheritance of (capr 1) allele; 2) selection against the (capr 1) allele as well in sexual crosses as during vegetative growth; 3) complete reversion of this selection by even low concentration of CAP. On the basis of their cytoplasmic inheritance and altered cytochrome spectra the five cytoplasmic mutations are assumed to be mitochondrial. Analysis of crosses between them allows to class them in 3 loci, 2 of which being closely linked.
Mol Gen Genet 1977 May 20
PMID:Mitochondrial genes in Podospora anserina: recombination and linkage. 88 68

1. Some in vitro studies were performed to elucidate the action of S-adenosyl-L-methionine (SAM) and thiosulphate on liver rhodanese, delta-amino-levulinic acid dehydratase (Al A-D) and cytochrome oxidase affected by cyanide in the experimental conditions. 2. SAM was unable to interact with the sulfur substituted rhodanese complex suggesting that SAM would blockade the thiosulphate binding sites on rhodanese. 3. Cyanide and thiosulphate inhibited ALA-D activity when both compounds were present in the incubation or the preincubation mixture. Cyanide binding on the enzyme was irreversible. 4. Cyanide inhibited cytochrome oxidase activity and the reversible nature of the binding was demonstrated by gel filtration. 5. SAM had no effect on either ALA-D or cytochrome oxidase activities.
Gen Pharmacol 1991
PMID:In vitro effect of cyanide, thiosulphate and S-adenosyl-L-methionine on the activity of rhodanese and other enzymes. 164 44

The Escherichia coli acid phosphatase gene appA is expressed in response to oxygen deprivation and is positively controlled by the product of appR (katF) which encodes a putative new sigma transcription-initiation factor. However, transcription of appA from its nearest promoter (P1) did not account for total pH 2.5 acid phosphatase expression and was not subject to regulation. The cloned region upstream of appA was extended and analyzed by insertions of transposon TnphoA and by fusions with lacZ. It contains two new genes, appC and appB, which both encode extracytoplasmic proteins. appC and appB are expressed from a promoter (P2) lying just upstream of appC. Both genes are regulated by oxygen, as is appA, and by appR gene product exactly as previously shown for appA. Analysis of the nucleotide sequence and of the origins of transcription have confirmed that the P2-appC-appB- (ORFX)-P1-appA region is organized on the chromosome as an operon transcribed clockwise from P2 and that P1 is a minor promoter for appA alone. Genes appC and appB encode proteins of Mr 58,133 and 42,377, respectively, which have the characteristics of integral membrane proteins. The deduced amino acid sequences of appC and appB show 60% and 57% homology, respectively, with subunits I and II of the E. coli cytochrome d oxidase (encoded by genes cydA and cydB). The notion that the AppC and AppB proteins constitute a new cytochrome oxidase or a new oxygen-detoxifying system is supported by the observation of enhanced sensitivity to oxygen of mutants lacking all three genes, cyo (cytochrome o oxidase), cyd (cytochrome d oxidase) and appB, compared to that of cyo cyd double mutants.
Mol Gen Genet 1991 Oct
PMID:A new oxygen-regulated operon in Escherichia coli comprises the genes for a putative third cytochrome oxidase and for pH 2.5 acid phosphatase (appA) 165 95

We report that the mitochondrial genome of Chlamydomonas moewusii has a 22 kb circular map and thus contrasts with the mitochondrial genome of Chlamydomonas reinhardtii, which is linear and about 6 kb shorter. Overlapping restriction fragments spanning over 90% of the C. moewusii mitochondrial DNA (mtDNA) were identified in a clone bank constructed using a Sau3AI partial digest of a C. moewusii DNA fraction enriched for mtDNA by preparative CsCl density gradient centrifugation. Overlapping Sau3AI clones were identified by a chromosome walk initiated with a clone of C. moewusii mtDNA. The mtDNA map was completed by Southern blot analysis of the C. moewusii mtDNA fraction using isolated mtDNA clones. Regions that hybridized to C. reinhardtii or wheat mitochondrial gene probes for subunit I of cytochrome oxidase (cox1), apocytochrome b (cob), three subunits of NADH dehydrogenase (nad1, nad2 and nad5) and the small and the large ribosomal RNAs (rrnS and rrnL, respectively) were localized on the C. moewusii mtDNA map by Southern blot analysis. The results show that the order of genes in the mitochondrial genome of C. moewusii is completely rearranged relative to that of C. reinhardtii.
Mol Gen Genet 1991 Dec
PMID:Cloning and characterization of the Chlamydomonas moewusii mitochondrial genome. 175 45

In a random collection of mit- mutations of the yeast strain 777-3A we find that deletions are exceptionally frequent in the OXI3 gene, a large mosaic gene coding for subunit I of cytochrome oxidase. About 10% of all oxi3-mutants carry the same macro-deletion, del-A, extending from the 5' non-translated leader of OXI3 to intron 5b of this gene. Determination of the respective wild-type sequences and of the del-A junction sequence revealed that the end-points of the deletion are in two GC clusters with 31 bp sequence identity which are located at a distance of 11.3 kb. We speculate that not only the sequence identity of the two GC clusters but also the palindromic structure of these putatively mobile elements of yeast mitochondrial DNA (mtDNA) plays a role in deletion formation.
Mol Gen Genet 1991 Apr
PMID:A GC cluster repeat is a hotspot for mit- macro-deletions in yeast mitochondrial DNA. 185 50

1. The effect of acute cyanide administration to mice in a lethal and a non-lethal dose and the anti-cyanide effect of S-adenosyl-L-methionine (SAM) and thiosulphate were investigated. 2. The poisoning action was determined by measuring cytochrome oxidase, rhodanese and delta-aminolevulinic acid dehydratase (ALA-D) activity. 3. The toxic metabolizing degree was investigated by measuring plasma and urine thiocyanate levels. 4. The state of the sulfane sulfur pool was investigated by determining cyanide labile-sulfur levels. 5. These results support the belief that rhodanese plays a fundamental role in the detoxification process only when high levels of cyanide are administered.
Gen Pharmacol 1990
PMID:Cyanide intoxication--III. On the analogous and different effects provoked by non-lethal and lethal challenged doses. 215 8

Administration of different doses of L-thyroxine (T4) and triiodo-L-thyronine (T3) in vivo in G. carnosus stimulated the activities of cytochrome oxidase, alpha-glycerophosphate dehydrogenase (alpha-GPDH), succinate dehydrogenase (SDH), and Mg2+ adenosine triphosphatase (Mg2+ ATPase) and inhibited the activity of malate dehydrogenase (MDH). While a low dose of thiouracil administration produced a stimulatory effect on cytochrome oxidase and alpha-GPDH activities, a higher dose of thiouracil significantly inhibited the activities of cytochrome oxidase, alpha-GPDH, SDH, Mg2+ ATPase, and MDH. Injection of T4 or T3 into thiouracil-treated animals significantly restored the stimulatory effect of thyroid hormones on oxidative enzyme activities. It is suggested that thyroid hormones in vivo increase and that thiouracil decreases the oxidative capacity of hepatic mitochondria of G. carnosus.
Gen Comp Endocrinol 1990 Aug
PMID:Stimulation of oxidative metabolism by thyroid hormones in an apodan amphibian, Gegenophis carnosus (Beddome). 216 65

Klebsiella pneumoniae synthesized only b-type and d-type cytochromes under the wide range of growth conditions tested, and reaction with CO revealed two potential oxidases. The o-type oxidase was produced only in the presence of O2 and appeared to be repressed by glucose. The d-type oxidase was, by contrast, produced only in the absence of measurable O2 (less than 1 microM), and was the only oxidase expressed in nitrogen-fixing conditions. It was extracted from the membrane, purified and shown to be similar to that from E. coli in being a heterodimer (subunits of Mr 52,000 and 35,000), in containing two distinguishable b haems and haem d (one or two molecules per molecule of oxidase), and in being able to react with O2 to give a stable oxygenated intermediate. The purified d-type cytochrome oxidase had a very high affinity for O2 (Km 20 nM; measured by the spectral properties of leghaemoglobin). It is proposed that this provides a role for this oxidase in lowering the O2 concentration to allow nitrogenase synthesis and function, and to provide a terminal oxidase to permit electron-transport-coupled ATP synthesis which supports the increase in efficiency of nitrogen fixation observed under microaerobic conditions.
J Gen Microbiol 1990 Jan
PMID:The purification, characterization and role of the d-type cytochrome oxidase of Klebsiella pneumoniae during nitrogen fixation. 219 Oct 76

We have sequenced the termini of the mitochondrial genome of Chlamydomonas reinhardtii and now present the DNA sequence of the gene for apocytochrome b. This gene is the thirteenth gene of the linear 15.8 kb DNA and appears to be the last one of the mt genome. The deduced protein sequence of 381 amino acid residues shows 56%, 48.6% and 48% identity with the apocytochrome b proteins of maize, Drosophila yakuba and mouse, respectively. RNA analysis reveals a transcript of about 1250 nucleotides. It is now possible to present the complete protein-coding capacity, the pattern of codon utilization for all eight protein genes, and the complete functional map of the mitochondrial 15.8 kb DNA of C. reinhardtii. One surprising feature is the absence of mitochondrial genes for ATPase and subunits II and III of cytochrome oxidase. No more than three tRNA genes appear to be present on the 15.8 kb mitochondrial DNA.
Mol Gen Genet 1990 Sep
PMID:Mitochondrial DNA of Chlamydomonas reinhardtii: the gene for apocytochrome b and the complete functional map of the 15.8 kb DNA. 225 Jun 48

The effects of oral chronic cyanide administration to mice were studied. Cyanide intoxication was confirmed by the increased levels of this poison and the concomitant inhibition of cytochrome oxidase activity in liver, brain, heart and blood. The detoxifying enzyme rhodanese was measured. The state of the sulfane sulfur pool was investigated by determination of the cyanide labile-sulfur levels. A clear correlation between rhodanese activity and sulfur content was obtained as a consequence of cyanide action. These results support the belief that rhodanese plays a fundamental role in the detoxification process of cyanide, in preventing cyanide reaching the target tissues.
Gen Pharmacol 1989
PMID:Cyanide intoxication--I. An oral chronic animal model. 254 8


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