Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.3.5.1 (succinate dehydrogenase)
 8,177 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

By using the continuous culture technique, the transition from aerobiosis to anaerobiosis and its effect on a number of enzymes has been investigated in Escherichia coli K-12. A decrease in the oxygen partial pressure below 28.0 mm of Hg resulted firstly in an increase of the respiratory enzymes (reduced nicotinamide adenine dinucleotide [NADH] oxidase, 2.53-fold; succinic dehydrogenase, 1.4-fold; cytochrome b(1), 3.91-fold; and cytochrome a(2), 2.45-fold) before the electron transport system gradually collapsed as cytochrome a(2), followed by cytochrome b(1), succinic dehydrogenase, and finally NADH oxidase decreased in activity. The change from respiration to fermentation was initiated well before the oxygen tension reached zero by the increase in levels of fructose diphosphate-aldolase, glucose 6-phosphate, and 6-phosphogluconate dehydrogenases and a decrease in 2-oxoglutarate dehydrogenase. Whem the dissolved oxygen tension reached zero, dry weight and CO(2) formation together with isocitrate dehydrogenase decreased, whereas acid production and phosphofructokinase synthesis started to increase. Enzymatic investigations revealed that the kinetics of the enzyme phosphofructokinase from strict aerobic cultures (6.9 ppm oxygen in solution) was adenosine triphosphate (ATP)-insensitive, whereas the same enzyme from anaerobic cultures was ATP-sensitive. A mechanism is proposed for the change from aerobiosis to anaerobiosis together with the occurring change in glucose regulation.
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PMID:Effect of oxygen on several enzymes involved in the aerobic and anaerobic utilization of glucose in Escherichia coli. 434 16

1. Hepatic glucose 6-phosphate dehydrogenase activity was increased in rats exposed to 5lb/in(2) (equivalent to 27000ft), 100% O(2) when compared with control animals in a 14.7lb/in(2) (sea level), air environment. Glyceraldehyde 3-phosphate dehydrogenase, isocitrate dehydrogenase, and succinate dehydrogenase were not affected by the 5lb/in(2), 100% O(2) environment. 2. Animals exposed to the hyperoxic environment consumed food, expired CO(2) and gained weight at the same rate as normoxic control animals. Additionally, blood glucose and liver glycogen concentrations were unchanged in the hyperoxic animals. The only readily apparent physiological difference in the hyperoxic animals was a decreased haematocrit. 3. The increase in glucose 6-phosphate dehydrogenase was eliminated by the injection of actinomycin D or cycloheximide. 4. Expiration of (14)CO(2) from [1-(14)C]glucose was approximately the same in hyperoxic and normoxic rats. However, (14)CO(2) expiration from [6-(14)C]glucose was markedly decreased in the animals exposed to the hyperoxic environment. 5. Calculations of the relative importance of the pentose phosphate pathway versus the tricarboxylic acid cycle plus glycolysis indicated that the livers from animals in the 5lb/in(2), 100% O(2) environment metabolized twice as much carbohydrate by way of the pentose phosphate pathway as did those from the sea-level air control animals. 6. In livers of rats exposed to 5lb/in(2), 100% O(2) the concentrations of pyruvate, citrate and 2-oxoglutarate were increased, that of isocitrate was slightly elevated, whereas the concentrations of succinate, fumarate and malate were decreased. 7. An inactivation of both tricarboxylic acid cycle lipoate-containing dehydrogenases, pyruvate and 2-oxoglutarate, under hyperoxic conditions is proposed. 8. The adaptive significance of the induction of glucose 6-phosphate dehydrogenase and the resultant production of NADPH under hyperoxic conditions is discussed.
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PMID:Biochemical adaptation of rat liver in response to marginal oxygen toxicity. 440 79

Sporulation mutants that were unable to incorporate uracil during the developmental period recovered this capacity with the addition of ribose and in most cases with the addition of glutamate. Of the mutants that responded to both ribose and glumate, all but three also responded to citrate, and all but five responded to acetate. One of the exceptional strains was deficient in aconitase and another one in aconitase and isocitrate dehydrogenase; both required glutamate for growth. For the mutants which did not respond to glutamate, the products made from (14)C-glutamate were determined by thin-layer chromatography. Significant differences were found which enabled the identification of mutant blocks. The deficiency of the corresponding enzyme activity was verified. Several mutants were deficient in alpha-ketoglutarate dehydrogenase, and one lacked succinic dehydrogenase. These mutants could still grow on glucose as sole carbon source, but not on glutamate. The intact Krebs cycle is therefore not required for vegetative growth of aerobic Bacillis subtilis, but it is indispensable for sporulation.
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PMID:Analysis of sporulation mutants. II. Mutants blocked in the citric acid cycle. 496 97

The genetic location of mutations affecting the citric acid cycle and the properties of mutants of Bacillus subtilis possessing these mutations have been examined. Genes coding for the component enzymes of the cycle were found to be unlinked to each other and thus do not form an operon. The mutational defect in a mutant lacking fumarase mapped between thr-5 and cysB3. Mutations causing inability to produce isocitrate dehydrogenase and succinate dehydrogenase were found to map between argA11 and leu-1. The alpha-ketoglutarate dehydrogenase mutations were mapped at the terminal end of the B. subtilis chromosome through a weak linkage in phage PBS-1 transduction of one class of these mutations of ilvA2 and metB4. A second class of alpha-ketoglutarate dehydrogenase mutations mapped closer to ilvA2 and metB4 but still terminal with respect to these markers. Aconitaseless mutants possessed mutations that could not be linked to any of the known transducing segments of the chromosome. An effect of mutation conferring loss of one enzyme of the cycle on the specific activity of the other enzymes in the cycle was observed.
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PMID:Citric acid cycle: gene-enzyme relationships in Bacillus subtilis. 499 71

The growth response of Listeria monocytogenes strains A4413 and 9037-7 to carbohydrates was determined in a defined medium. Neither pyruvate, acetate, citrate, isocitrate, alpha-ketoglutarate, succinate, fumarate, nor malate supported growth. Furthermore, inclusion of any of these carbohydrates in the growth medium with glucose did not increase the growth of Listeria over that observed on glucose alone. Resting cell suspensions of strain A4413 oxidized pyruvate but not acetate, citrate, isocitrate, alpha-ketoglutarate, succinate, fumarate, or malate. Cell-free extracts of strain A4413 contained active citrate synthase, aconitate hydratase, isocitrate dehydrogenase, malate dehydrogenase, fumarate hydratase, fumarate reductase, pyruvate dehydrogenase system, and oxidases for reduced nicotinamide adenine dinucleotide and reduced nicotinamide adenine dinucleotide phosphate. The alpha-ketoglutarate oxidation system, succinate dehydrogenase, isocitrate lyase, and malate synthase were not detected. Cytochromes were not detected. The data suggest that strain A4413, under these conditions, utilizes a split noncyclic citrate pathway which has an oxidative portion (citrate synthase, aconitate hydratase, and isocitrate dehydrogenase) and a reductive portion (malate dehydrogenase, fumarate hydratase, and fumarate reductase). This pathway is probably important in biosynthesis but not for a net gain in energy.
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PMID:Citrate cycle and related metabolism of Listeria monocytogenes. 499 14

The activities of the eight citric acid-cycle enzymes of rat bone-marrow cells were determined along with several other mitochondrial and non-mitochondrial enzymes. Four of the citric acid-cycle enzymes (aconitase, succinyl-CoA thiokinase, alpha-oxoglutarate dehydrogenase and succinate dehydrogenase) have closely similar low activities; two [isocitrate dehydrogenase (NAD) and citrate synthase] have intermediate activities; the remaining two (malate dehydrogenase and fumarase) have high activities. The other enzymes surveyed also exhibited a spread of three orders of magnitude, the mitochondrial enzymes showing no less variation than the others.
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PMID:The activities of the citric acid-cycle enzymes in rat bone-marrow cells. 566 55

Treatment of rat liver mitochondria with digitonin followed by differential centrifugation was used to resolve the intramitochondrial localization of both soluble and particulate enzymes. Rat liver mitochondria were separated into three fractions: inner membrane plus matrix, outer membrane, and a soluble fraction containing enzymes localized between the membranes plus some solublized outer membrane. Monoamine oxidase, kynurenine hydroxylase, and rotenone-insensitive NADH-cytochrome c reductase were found primarily in the outer membrane fraction. Succinate-cytochrome c reductase, succinate dehydrogenase, cytochrome oxidase, beta-hydroxybutyrate dehydrogenase, alpha-ketoglutarate dehydrogenase, lipoamide dehydrogenase, NAD- and NADH-isocitrate dehydrogenase, glutamate dehydrogenase, aspartate aminotransferase, and ornithine transcarbamoylase were found in the inner membrane-matrix fraction. Nucleoside diphosphokinase was found in both the outer membrane and soluble fractions; this suggests a dual localization. Adenylate kinase was found entirely in the soluble fraction and was released at a lower digitonin concentration than was the outer membrane; this suggests that this enzyme is localized between the two membranes. The inner membrane-matrix fraction was separated into inner membrane and matrix by treatment with the nonionic detergent Lubrol, and this separation was used as a basis for calculating the relative protein content of the mitochondrial components. The inner membrane-matrix fraction retained a high degree of morphological and biochemical integrity and exhibited a high respiratory rate and respiratory control when assayed in a sucrose-mannitol medium containing EDTA.
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PMID:Enzymatic properties of the inner and outer membranes of rat liver mitochondria. 569 70

Enzyme histochemical methods were performed on sporozoite infected liver tissue of rats in order to gain insight into the nutrition and metabolism of exoerythrocytic forms of Plasmodium berghei. The following enzymes were demonstrated in the hepatocytic stages of the parasites, obtained 41 and 48 h after inoculation of sporozoites: acid phosphatase, cytochrome oxidase, NADH-tetrazolium reductase, succinate dehydrogenase, NAD+ and NADP+ dependent isocitrate dehydrogenase, NADP+-dependent malate dehydrogenase, lactate dehydrogenases, 6-phosphogluconate dehydrogenase and glucose-6-phosphate dehydrogenases and alpha-glycerol-phosphate dehydrogenase. The results suggest that a conventional Embden-Meyerhoff pathway, pentose phosphate pathway and Krebs' citric acid cycle may in part be present in these exoerythrocytic parasites. Alkaline phosphatase, nucleoside polyphosphatase, 5' nucleotidase, glucose-6-phosphatase, alpha-glucan phosphorylase, NAD+ dependent malate dehydrogenase, amino-peptidase M and non-specific esterases were not detected by our techniques in the parasite. The enzyme distribution of this intrahepatocytic malaria parasite revealed by histochemistry is compared with the enzyme distribution in the other phases of the parasite's life cycle.
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PMID:Histochemical observations on the exoerythrocytic malaria parasite Plasmodium berghei in rat liver. 608 94

Acetate oxidation by sulphate was studied with desulfobacter postgatei. Cell extracts of the organism were found to contain high activities of the following enzymes: citrate synthase, aconitase, isocitrate dehydrogenase, alpha-ketoglutarate dehydrogenase, succinate dehydrogenase, fumarase, malate dehydrogenase and pyruvate synthase. It is concluded that acetate oxidation with sulphate in D. postgatei proceeds via the citric acid cycle with the synthesis of pyruvate from acetyl CoA and CO2 as an anaplerotic reaction. The apparent Ks for acetate oxidation by D. postgatei as determined in vivo was near 0.2 mM. The apparent Ks for acetate fermentation to methane and CO2 by methanosarcina barkeri was 3 mM. The significantly lower ks for acetate of the sulphate reducer explains why methane formation from acetate in natural habitats is apparently inhibited by sulphate.
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PMID:Dissimilatory sulphate reduction with acetate as electron donor. 612 36

Using histochemical techniques, the reactivities of selected enzymes and other metabolic components were examined in the myocardium, coronary arteries, and coronary arterioles of normal, two-week-sympathectomized, and sham-operated canine hearts. There were no differences in the histochemistry of coronary arteries in any of the hearts, but important differences were noted in the myocardium and especially in the arterioles. The reactivities of the enzyme glucose-6-phosphate dehydrogenase and the nucleic acids were increased in arterioles of the sympathectomized heart, possibly indicating an increased protein synthesis. The reactivities of succinate dehydrogenase, NAD-isocitrate dehydrogenase, and cytochrome oxidase were reduced in myocardium and arterioles of sympathectomized hearts as well as in arterioles of sham-operated hearts; the changes were greater in the sympathectomized arterioles where there was also observed an increase in reactivity of lactate dehydrogenase. These findings suggest a depression in aerobic metabolic capacity and, in the case of the sympathectomized arteriole, imply a possible shift in adaptation from aerobic to anaerobic metabolism.
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PMID:The myocardium and its vasculature: a histochemical comparison of the normal and chronically sympathectomized dog heart. 615 74


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