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)

In a detailed study focused on the methodological problems in dehydrogenase histochemistry [e.g., fixation, diffusion of enzymes and of reduced inermediates, conversion of NADPH and NADP to NADH and NAD, respectively, penetration of tetrazolium salt and formazan substantivity, 'nothing dehydrogenase' reaction, use of exogenous CoQ10 and of flavoprotein substitute (PMS)], the distribution and activity of succinate dehydrogenase, NAD(P)H-tetrazolium reductase, glucose-6-phosphate dehydrogenase, lactate dehydrogenase (H and M types), and of L-glutamate dehydrogenase (E.C.1.4.1.2 and E.C.1.4.1.3) have been investigated in the rat cerebellum. It was evident from the study that reliable results could only be obtained if all the aforementioned factors had been considered. The image of actual concentration of SDH in the neuropil of the molecular layer could only be recorded by adding CoQ10, while other structures exhibited greater balance between SDH and endogenous mitochondrial CoQ. Contrary to previous studies, a reversed localization of the activity of G-6-PDH and LDH was noticed. The elements of molecular and Purkinje layers were rich in G-6-PDH, while the granular layer was nearly depleted. The actual level of LDH could only be recorded if NADH-tetrazolium reductase was bypassed with PMS. The H and M types of LDH coexisted in the three cortical layers, the H type being prevalent and the M type attaining its highest level in synaptic glomeruli followed by the structures of the molecular layer and the Purkinje cells. High activity of GDH was noticed in Bergmann glia followed by synaptic glomeruli, while most other structures showed weak to moderate activity. The two GDH types coexisted in all structures showing activity, except for Bergmann cells, which only showed presence of the E.C. 1.4.1.3 type. Furthermore, Bergmann glia was exceptional by showing no activity of SDH and LDH, but strong activity of G-6-PDH and NADPH-tetrazolium reductase. The granular cells were exceptional by showing weak or no activity of all enzymes in question.
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PMID:Methodological aspects of the histochemical localization and activity of some cerebellar dehydrogenases. 66 87

The activities of twelve enzymes were measured in crude extracts from cells of Escherichia coli K-10 grown aerobically or anaerobically in a defined medium in the presence or absence of nitrate. The activities of isocitrate dehydrogenase, aconitate hydratase, 2-oxoglutarate dehydrogenase, malate dehydrogenase, malic enzyme, and D-lactate dehydrogenase (NAD+-independent) were found to be higher in cells grown in nitrate respiration than in those in fermentation, but lower than in those in respiration. This finding may explain the incomplete oxidation in nitrate respiration and, on the other hand, suggests the operation of the tricarboxylic acid even under these conditions. The activities of succinate dehydrogenase and alcohol dehydrogenase in relation to the formation of fermentation product were as high in cells grown in fermentation as in those in respiration and were low in those in nitrate respiration. However, that ratio of the activities in the latter case to the activities in respiration was the same as the ratio for most enzymes in the tricarboxylic acid cycle. The level of lactate dehydrogenase (NAD+-dependent) was not affected by nitrate respiration but its activity in the extract was inhibited by nitrate and nitrite. The absence of lactate in the anaerobic culture with nitrate may be due to this inhibition as well as NADH oxidation by nitrate. Levels of glucose-6-phosphate dehydrogenase and glutamate dehydrogenase were not altered by the growth conditions and that of pyruvate dehydrogenase was low only in cells grown in fermentation.
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PMID:Effect of nitrate reduction on the enzyme levels in carbon metabolism in Escherichia coli. 77 52

Chemostat cultures of E. coli K-12 revealed that the metabolic change from respiration to aerobic fermentation can be obtained with increasing specific growth rate at low glucose input concentration (0.1%), or increasing glucose input concentrations at low specific growth rate (0.1 h-1). Both effects do not affect biomass formation. The metabolic change is not related to a pathway switch of glucose utilization. The increase in specific growth rate causes suppression of succinate dehydrogenase, and NADH oxidase, whereas glucose increases cause suppression of succinate dehydrogenase, cytochrome a and 2-ketoglutarate dehydrogenase. Both phenomena are reflected in the specific oxygen uptake rate, specific carbon dioxide production rate and respiratory quotient values. Growth limitation could be related to a maximal glucose uptake rate of the cell and thus constitutes an entirely different effect caused by high glucose input concentration.
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PMID:Effect of specific growth rate and glucose concentration on growth and glucose metabolism of Escherichia coli K-12. 80 Oct 33

Organ cultures of malignant tumours were histochemically and electronmicroscopically investigated. There was established that follows enzymes show a little activity in cultured tumour cells after 24 and 48 h: succinate dehydrogenase, alkaline phosphatase, adenosine triphosphatase, and nonspecific esterase, whereas NADH-diophorase, lactate dehydrogenase, and acid phosphatase show an essentially higher activity after termination of the cultivation. However, in comparison with the primare tissue, the activities of the last mentioned enzymes are clearly decreased in cultured tumour cells after termination of the cultivation. No changes of cell structures have electronmicroscopically been observed on these cultures of malignant tumours.
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PMID:[Histochemical and ultrastructural investigations on organ culture of malignant tumors (author's transl)]. 81 69

In the paper we observed histochemically the distribution and activity of 16 enzymes in the normal rat gastric mucosa. The lysosomal enzymes were demonstrated by the method of semipermeable membranes (LOJDA 1972). At the proof of dehydrogenases aqueous and gel media were used. The parietal cells of the gastric mucosa contained a moderate activity of acid phosphatase, E-600 resistant esterase, and only a very slight activity of beta-glucuronidase and N-acetyl-beta-D-glucosaminidase. The macrophages of the interstice contained a high activity of beta-glucruonidase, acid phosphatase, E-600 resistant esterase and a low activity of N-acetyl-beta-D-glucosaminidase. The chief cells of the rat gastric mucosa, in contrast to the human, did not contain nonspecific esterase and also in them acid phosphatase was mostly lacking. The alkaline phosphatase was found only in the endothelium of the capillaries of the gastric mucosa. The parietal cells contained high activities of succinate dehydrogenase, alpha-glycerophosphate dehydrogenase, beta-hydroxybutyrate dehydrogenase, NADH tetrazolium reductase, a lower activity of NADPH tetrazolium reductase, as well as other soluable dehydrogenases. At the examination of dehydrogenases using aqueous as well as gel media with PMS during optimal short incubation periods, we found more and less active forms of parietal cells. The different oxidoreductase capacity of parietal cells in normal rat gastric mucosa can point to their unequal-functional load at the production of hydrochloric acid. The findings obtained are compared with the findings in older papers concerning different experimental animals and with the distribution of enzymes in the human gastric mucosa.
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PMID:Histochemical localization of enzymes in the normal rat gastric mucosa using the technique of the semipermeable membranes and the other methods. 82 7

Cephalothin inhibits the activities of platelet enzymes, succinic dehydrogenase and NADH-cytochrome-c-reductase in patients with chronic renal failure. Two hours after Cephalothin administration the return of enzyme activities to baseline values was dependent on the severity of the chronic renal failure, and the higher the serum-creatinine concentration, the slower was the return to original enzyme activities.
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PMID:[Cephalothin and platelet enzymes in chronic renal failures]. 82 21

In the presented study the influence of freezing and freeze-drying on enzyme activity is described. Attention is paid to 16 enzymes which can be used for quantitative enzyme histochemical techniques. With the exception of succinate dehydrogenase only, no significant inactivation during freezing and freeze-drying procedures could be demonstrated with lactate dehydrogenase, malate dehydrogenase (NAD+), malate dehydrogenase (decarboxylating) (NADP+), isocitrate dehydrogenase (NADP+), glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, NADH-oxydoreductase, mitochondrial glycerol-3-phosphate dehydrogenase, cytochrome c oxidase, phosphoglucomutase, glucosephosphate isomerase, glucose-6-phosphatase, acid phosphatase, beta-glucuronidase and non specific aryl esterase. Therefore, the results supply a sound foundation for those quantitative enzyme histochemical techniques in which tissue specimens are frozen or frozen-dried before enzyme estimations are performed.
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PMID:The influence of freezing and freeze-drying of tissue specimens on enzyme activity. 87 Apr 61

The topography of the inner mitochondrial membrane was investigated using inhibitors of electron transport on preparations of beef heart mitochondria and electron transport particles of opposite orientation. Reductions of juglone, ferricyanide, indophenol, coenzyme Q, duroquinone, and cytochrome c by NADH are inhibited to different extents on both sides of the membrane by the impermeant hydrophilic chelators bathophenanthroline sulfonate and orthophenanthroline. The extent of inhibition for each acceptor increased in the order given. At least two chelator-sensitive sites are present on each membrane face between the flavoprotein and coenzyme Q and a chelator-sensitive site is present on the matrix face between the sites of coenzyme Q and duroquinone interaction. Duroquinol oxidation in mitochondria only is stimulated by bathophenanthroline sulfonate. Juglone reduction is stimulated in electron transport particles (only) by p-hydroxymercuribenzenesulfonate, but after mercurial treatment, juglone reduction in both particles and mitochondria is more sensitive to bathophenanthroline sulfonate. Succinate dehydrogenase components are inhibited by hydrophilic orthophenanthroline or bathophenanthroline sulfonate in mitochondria only. Electron flow between the dehydrogenases of succinate and NADH occurs via a chelator-sensitive site located on the matrix face of the membrane. Inter-complex electron flow is prevented by rotenone or thenoyltrifluoroacetone. The lack of succinate-indophenol reductase inhibition by bathophenanthroline sulfonate in the presence of rotenone or thenoyltrifluoroacetone indicates that the rotenone-sensitive site may be located on the matrix face and demonstrates that electrons flow between the NADH and succinate dehydrogenases via a hydrophilic chelator and rotenone-thenoyltrifluoroacetone-sensitive site on the matrix face of the membrane. Inhibiton by hydrophilic chelators only in mitochondria indicates that succinate dehydrogenase as well as NADH dehydrogenase has a transmembranous orientation.
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PMID:Inhibition of mitochondrial electron transport by hydrophilic metal chelators. Determination of dehydrogenase topography. 94 64

Two freshwater bacteria, a Pseudomonas sp. and a Spirillum sp., were grown in continuous culture under steady-state conditions in L-lactate-, succinate-, ammonium- or phosphate-limited media. In Pseudomonas sp., NAD-independent and NAD-dependent L-lactate dehydrogenases, aconitase, isocitrate dehydrogenase and glucose 6-phosphate dehydrogenase activities increased up to 10-fold as the dilution rate (D) was decreased from 0.5 to 0.02 h-1, regardless of whether the growth-limiting nutrient was carbon, ammonium or phosphate. In contrast, 2-oxoglutarate dehydrogenase and succinate dehydrogenase activities were not influenced by D, and NADH oxidase activity increased with D. Spirillum sp. gave different results in some respects, but it also exhibited an increase in the activity of several enzymes at low D values. Such increases may emanate from release of catabolite repression, and catabolite repressors for the five enzymes in Pseudomonas sp. showing such increases are probably compounds of carbon, nitrogen and phosphorus. It is likely that increased enzyme syntheses in low D cultures represent the normal physiological state for bacteria in aquatic environments where growth occurs slowly under nutrient limitations. Such increases probably permit a more effective utilization of nutrients present at sub-saturating concentrations.
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PMID:Influence of dilution rate on enzymes of intermediary metabolism in two freshwater bacteria grown in continuous culture. 95 May 55

The activity of the succinate dehydrogenase-coenzyme Q10 reductase from 120 diabetic patients was significantly lower (P less than 0.001) and the per cent deficiency was significantly higher (P less than 0.001) than that of the controls. The diabetes of 37 patients was controlled by diet; the enzyme activity was lower (P less than 0.001) and the deficiency was higher (P less than 0.02) than for controls. In decreasing effectiveness, Dymelor, Glyburide, Phenformin and Tolazamide inhibited the COQ10-enzyme, NADH-oxidase. Tolbutamide, Glypizide, and Chlorpropamide were noninhibitory to succinoxidase and NADH-oxidase. Patients receiving Tolazamide and Phenformin showed a higher incidence (P less than 0.001 to P less than 0.05) of COQ10-deficiency than patients controlled by diet or normal controls. Certain diabetic patients controlled by diet may have a deficiency of COQ10 which may be enhanced by the inhibition by certain commonly used antidiabetic drugs of COQ10-enzymes. A deficiency of COQ10 in the pancreas could impair bioenergetics, the generation of ATP, and the biosynthesis of insulin.
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PMID:Bioenergetics in clinical medicine. XI. Studies on coenzyme Q and diabetes mellitus. 107 May 15


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