Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: 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)

A succinate-coenzyme Q reductase (complex II) was isolated in highly purified form from Ascaris muscle mitochondria by detergent solubilization, ammonium sulfate fractionation and gel filtration on a Sephadex G-200 column. The enzyme preparation catalyzes electron transfer from succinate to coenzyme Q1 with a specific activity of 1.2 mumol coenzyme Q1 reduced per min per mg protein at 25 degrees C. The isolated complex II is essentially free of NADH-ferricyanide reductase, reduced CoQ2-cytochrome c reductase and cytochrome c oxidase and consists of four major polypeptides with apparent molecular weights of 66 000, 27 000, 12 000 and 11 000 and two minor ones with Mr of 36 000 and 16 000. The complex II contained cytochrome b-558, a major constituent cytochrome of Ascaris mitochondria, at a concentration of 3.6 nmol per mg protein, but neither other cytochromes nor quinone. The cytochrome b-558 in the complex II was reduced with succinate. In the presence of Ascaris NADH-cytochrome c reductase (complex I-III) (Takamiya, S., Furushima, R. and Oya, H. (1984) Mol. Biochem. Parasitol. 13, 121-134), the cytochrome b-558 in complex II was also reduced with NADH and reoxidized with fumarate. These results suggest the cytochrome b-558 to function as an electron carrier between NADH dehydrogenase and succinate dehydrogenase in the Ascaris NADH-fumarate reductase system.
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PMID:Electron-transfer complexes of Ascaris suum muscle mitochondria. II. Succinate-coenzyme Q reductase (complex II) associated with substrate-reducible cytochrome b-558. 375 51

In order to locate sites of action of thyroid hormone on mitochondrial oxidative phosphorylation we have used an experimental application of control analysis as previously described [Groen, Wanders, Westerhoff, Van der Meer & Tager (1982) J. Biol. Chem. 257, 2754-2757]. Rat-liver mitochondria were isolated from hypothyroid rats or from hypothyroid rats 24 h after treatment with a single dose of 3,3',5-triiodothyronine (T3). The amount of control exerted by four different steps on State-3 respiration with succinate as respiratory substrate was quantified by using specific inhibitors. The hormone treatment resulted in an increase in the flux control coefficient of the adenine nucleotide translocator, the dicarboxylate carrier and cytochrome c oxidase and a decrease in the flux control coefficient of the bc1-complex. The results of this analysis indicate that thyroid hormone treatment results in an activation of the bc1-complex and of at least one other enzyme, possibly succinate dehydrogenase. Measurement of the extramitochondrial ATP/ADP ratio at different rates of respiration (induced by addition of different amounts of hexokinase in the presence of glucose and ATP) showed that the adenine nucleotide translocator operates at a higher (ATP/ADP)out after T3 treatment, which supports previous reports on stimulation of this step by thyroid hormone.
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PMID:Effects of thyroid hormone on mitochondrial oxidative phosphorylation. 397 64

1. Increased specific activities of cytochrome c oxidase, catalase, succinate dehydrogenase, succinate-cytochrome c oxidoreductase, NADH-cytochrome c oxidoreductase and malate dehydrogenase were observed during glucose de-repression of Schizosaccharomyces pombe. 2. The cell-cycle of this organism was analysed by three different methods: (a) harvesting of cells at intervals from a synchronous culture, (b) separation of cells by rate-zonal centrifugation into different size classes and (c) separation of cells by isopycnic-zonal centrifugation into different density classes. 3. Measurement of enzyme activities during the cell-cycle showed that all the enzymes assayed [cytochrome c oxidase, catalase, acid p-nitrophenylphosphatase, NADH-dehydrogenase, NADH-cytochrome c oxidoreductase, NADPH-cytochrome c oxidoreductase, succinate dehydrogenase, malate dehydrogenase, isocitrate dehydrogenase (NADP) and fumarate hydratase] show periodic expression as ;peaks'. 4. Cytochrome c oxidase shows a single maximum at 0.67 of a cycle, whereas succinate dehydrogenase exhibits two maxima separated by 0.5 of a cell-cycle. 5. All other enzymes assayed showed two distinct maxima per cell-cycle; for catalase, malate dehydrogenase and NADPH-cytochrome c oxidoreductase there is the possibility of multiple fluctuations. 6. The single maximum of cytochrome c oxidase appears at a similar time in the cycle to one maximum of each of the other enzymes studied, except for NADH dehydrogenase. 7. These results are discussed with reference to previous observations on the expression of enzyme activities during the cell-cycle of yeasts.
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PMID:Oscillations of enzyme activities during the cell-cycle of a glucose-repressed fission-yeast Schizosaccharomyces pombe 972h-. 414 72

1. The specific activities of cytochrome c oxidase, catalase, succinate dehydrogenase, succinate-cytochrome c oxidoreductase, NADH-cytochrome c oxidoreductase, and NADPH-cytochrome c oxidoreductase in mid-exponential-phase batch cultures of glycerol-grown Schizosaccharomyces pombe indicated that the organisms were catabolite-de-repressed. 2. In cultures growing synchronously in the presence of glycerol as sole carbon source, the respiration rate showed two abrupt increases at about 0.45 and 0.95 of the cell-cycle and remained constant in the periods between successive rises. 3. Catalase, succinate dehydrogenase, NADH-cytochrome c oxidoreductase and acid p-nitrophenyl-phosphatase all showed peak patterns of expression in synchronous cultures. 4. Cytochrome c oxidase and cytochromes a+a(3) both showed step patterns of expression with two rises per cell-cycle. 5. Cytochromes c(548), b(554) and b(560) all followed similar time-courses in step patterns of expression, but these were distinct from, and more complex than, that of cytochromes a+a(3). 6. These results are compared with those previously obtained with glucose-grown cultures, and the part played by catabolite repression in the expression of respiratory activities in the cell-cycle is assessed.
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PMID:Changes in respiratory activities during the cell-cycle of the fission yeast Schizosaccharomyces pompe 972h--growing in the presence of glycerol. 415 30

1. Changes in the amounts and distribution of protein and respiratory enzymes have been estimated during the life cycle of the fly Lucilia cuprina. 2. The fully fed larva contains about 7mg. of protein, the pupa and newly emerged fly about 4mg., and the mature adult about 3mg. 3. There are two periods of incorporation of protein into particles at the expense of the soluble protein; the first, immediately after pupation, may store protein (0.5mg./insect) for use in adult development; the second, over the period of emergence, was due mainly to the development of the thoracic mitochondria of the adult (0.7mg./insect). 4. In the thorax, cytochrome c oxidase and the dehydrogenases for glycerophosphate, isocitrate (NAD-dependent), succinate and malate appeared initially in small particles (less than 1mu in diameter). 5. In adult development these enzymes were redistributed so that in the mature fly most of the activity was present in larger particles (1-10mu in diameter). 6. During this redistribution the specific activity (mul. of oxygen/hr./mg. of protein) of glycerophosphate dehydrogenase in the small particles was 690 at 1(1/2) days before emergence, 955 at emergence and 980 at 7 days after emergence; the corresponding values for the large particles were 164, 760 and 1220. 7. In the mature fly the highest specific activities (mul. of oxygen/hr./mg. of protein) estimated were: glycerophosphate dehydrogenase 1380, isocitrate dehydrogenase (NAD-dependent and requiring ADP and Mg(2+)) 408, succinate dehydrogenase 122, malate dehydrogenase 190, and cytochrome c oxidase 1360. 8. The results are considered in relation to the development of the flight-muscle sarcosomes.
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PMID:Aspects of the development of flight-muscle sarcosomes in the sheep blowfly, Lucilia cuprina, in relation to changes in the distribution of protein and some respiratory enzymes during metamorphosis. 429 61

Saccharomyces cerevisiae was grown in batch culture over a wide range of oxygen concentrations, varying from the anaerobic condition to a maximal dissolved oxygen concentration of 3.5 muM. The development of cells was assayed by measuring amounts of the aerobic cytochromes aa(3), b, c, and c(1), the cellular content of unsaturated fatty acids and ergosterol, and the activity of respiratory enzyme complexes. The half-maximal levels of membrane-bound cytochromes aa(3), b, and c(1), were reached in cells grown in O(2) concentrations around 0.1 muM; this was similar to the oxygen concentration required for half-maximal levels of unsaturated fatty acid and sterol. However, the synthesis of ubiquinone and cytochrome c and the increase in fumarase activity were essentially linear functions of the dissolved oxygen concentration up to 3.5 muM oxygen. The synthesis of the succinate dehydrogenase, succinate cytochrome c reductase, and cytochrome c oxidase complexes showed different responses to changes in O(2) concentration in the growth medium. Cyanide-insensitive respiration and P(450) cytochrome content were maximal at 0.25 muM oxygen and declined in both more anaerobic and aerobic conditions. Cytochrome c peroxidase and catalase activities in cell-free homogenates were high in all but the most strictly anaerobic cells.
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PMID:Respiratory development in Saccharomyces cerevisiae grown at controlled oxygen tension. 435 79

Sixteen male subjects (20-31 yr) trained for 8 wk on cycle ergometers. Eight of the subjects were treated during the training period with the beta-adrenoceptor blocker propranolol (160 mg/day). During all pre-and posttraining tests, subjects were uninfluenced by the medication. Training-induced increases in VO2max and decreases in blood lactate and norepinephrine concentrations at submaximal exercise were not different between the beta-blockade and the placebo groups. The activities of the mitochondrial enzymes citrate synthase (CS), succinate dehydrogenase (SDH), cytochrome c oxidase (Cyt-c-ox), and 3-hydroxyacyl-CoA dehydrogenase (HAD) in the quadriceps femoris muscle increased significantly (P less than 0.01) with training (beta-blockade group, +47, +33, +38, and 22%; placebo group, +75, 70, +87, and +63%, respectively). Cyt-c-ox and HAD increased significantly more in the placebo group than in the beta-blockade group, while a tendency to an increase was noted for SDH. Muscle capillary density increased similarly (+17-19%) with training in the two groups (P less than 0.01). In conclusion, subjects training under the influence of a therapeutic level of beta-adrenergic blockade show marked increases in both the respiratory capacity and the capillary supply of the engaged skeletal muscles. However, the increase in muscle mitochondrial enzymes may be less apparent than in the normal state.
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PMID:Beta-adrenergic blockade and training in human subjects: effects on muscle metabolic capacity. 608 81

We have studied a 17-year-old girl with lactic acidosis (3-18 mEq/liter) and progressive muscle weakness since 9 years of age. Morphological findings in muscle were of a typical ragged red myopathy with multiple collections of bizarre mitochondria, some containing paracrystalline inclusions. The carnitine content of serum and muscle was normal, as were the activities of carnitine palmitoyltransferase, carnitine octanoyltransferase, and carnitine acetyltransferase in the patient's muscle. Measurement of the enzymes of oxidative phosphorylation in both crude muscle homogenates and mitochondrial fractions showed close to normal activities of cytochrome c oxidase, succinate dehydrogenase, and ATPase. In contrast, succinate cytochrome c reductase activity was greatly reduced in the patient, being 0.035 mumol/min/g tissue in whole muscle (controls 1.16 +/- 0.47 mumol/min/g tissue) and 8 nmol/min/mg protein in the mitochondria (control, 340 nmol/min/mg protein). Rotenonesensitive NADH-cytochrome c reductase was also undetectable in the patient's mitochondria. Spectral analysis of cytochromes showed decrease of reducible cytochrome b to 16% of the control. These results indicate a defect of ubiquinol-cytochrome c reductase or the cytochrome bc1 segment (complex III) of the electron transport chain. Antibody-binding studies of the individual components of complex III showed additional deficiencies of core proteins I and II and peptide VI, indicating a more widespread defect of complex III than was evident from spectral analysis and enzyme activity measurements alone. Urine organic acid analysis after fasting and following a medium chain triglyceride load showed unusually high levels of lactate and 3-hydroxybutyrate, lower than expected levels of acetoacetate and dicarboxylic acids, and the presence of several other metabolites suggesting a disturbed citric acid cycle and redox state.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Lactic acidosis and mitochondrial myopathy associated with deficiency of several components of complex III of the respiratory chain. 609 35

Specific effects of various catecholamines as well as functional dependence of mitochondrial enzymes activity on catecholamine metabolism were studied. Dopamine activated cytochrome c oxidase in heart mitochondria and decreased this enzymatic activity in liver tissue. Noradrenaline and adrenaline activated cytochrome c oxidase in liver, brain and kidney tissues. The effect of dopamine on cytochrome c oxidase was prevented by activation of dopamine beta-hydroxylase. Increased activity of monoamine oxidase caused accumulation of catecholamine metabolites, which inhibited the succinate dehydrogenase activity in liver tissue and the cytochrome c oxidase activity in brain, kidney and liver tissues. In the catecholamine regulation of succinate dehydrogenase and ATPase activities in all the tissues studied as well as of cytochrome c oxidase activity in heart tissue the quinoid oxidation products were apparently involved.
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PMID:[Catecholamine metabolism and mitochondrial enzyme activity]. 612 94

The effects of zinc on the enzymes of hepatic mitochondria were investigated in rats that had been given zinc sulfate (10 mg Zn2+/100 g body wt) p.o. Administration of zinc caused a marked elevation of succinate dehydrogenase, glutamate dehydrogenase, cytochrome c oxidase and ATPase activities, whereas it did not cause significant changes in pyruvate carboxylase, malate dehydrogenase and isocitrate dehydrogenase activities. The effect of zinc as a function of time was greatest on succinate dehydrogenase. Zinc also produced a marked elevation of ATP concentration in the hepatic cytosol and a corresponding increase in ATPase activity in the hepatic mitochondria. Zinc content of the inner membrane of mitochondria was raised significantly by administration of zinc. The removal of zinc by washing in 10 mM EDTA caused a significant decrease of the increased succinate dehydrogenase activity caused by administration of zinc, while it did not lower ATPase activity. The addition of zinc in amounts of 10-10(3) ng Zn2+ per mg protein produced a significant increase in succinate dehydrogenase activity in the inner membrane of mitochondria, whereas ATPase activity was elevated significantly at 10(3)-10(4) ng Zn2+ per mg protein, indicating that zinc activated succinate dehydrogenase more sensitively than ATPase. The present investigation suggests that zinc taken up by hepatic mitochondria stimulates the electron transport system and oxidative phosphorylation and, as a result, increases the ATP concentration in the hepatic cytosol.
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PMID:Role of zinc as an activator of mitochondrial function in rat liver. 621 62


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