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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)
The purpose of this work was in investigate the capability of cell extracts of Escherichia coli and E. coli treated with colicin K to catalyze the following energy-dependent reverse transhydrogenase reaction: NADP + NADH + ATP in equilibrium
NADPH
+ NAD +ADP + Pi. Under anaerobic conditions this reaction requires the presence of a specific portion of the electron transport chain, a functional energy coupling system, including an adenosine triphosphatase, enzyme, and ATP as energy source. The ATP-linked reaction was partially inhibited in French press extracts of E. coli K-12 C600 cells that had been pretreated with colicin K but not in extracts from similarly treated cells of a colicin-tolerant mutant. Ultracentrifugation of extracts yielded particulate fractions competent in catalyzing the reaction; this reaction is substantially inhibited in fractions from colicin-treated cells. The extent of inhibition increased with increasing concentration of colicin. Supernatants also supported ATP-linked formation of
NADPH
, but this reaction was insensitive to the colicin effect. A comparison between the requirement of the reaction in supernatant and particulate fractions suggests that the reaction in the supernatant is different from the one inhibited by colicin. The ATP-hydrolyzing ability of particulate fractions from the control or treated bacteria was identical. Likewise, the electron transport chain was not affected by colicin treatment, as evidenced from lack of effect on NADH oxidase,
succinic dehydrogenase
, and
NADPH
-NAD transhydrogenase. It is concluded that colicin K interferes with the coupling of ATP the utilization of the intermediate for the ATP-linked transdehydrogenase reaction.
...
PMID:Effect of colicin K on a membrane-associated, energy-linked function. 0 29
Trout liver homogenates metabolized di-2-ethylhexyl phthalate (DEHP) to monoethylhexyl phthalate (MEHP) without added
NADPH
and to MEHP and more polar metabolites with added
NADPH
. Both hydrolysis and oxidative metabolism of DEHP were inhibited by piperonyl butoxide. The 10,000g pellet, 100,000g pellet and 100,000g supernatant fraction from liver homogenates all catalyzed the hydrolysis of DEHP and all but the 100,000g supernatant fraction showed the shift to more polar metabolites with added
NADPH
; serum also catalyzed the hydrolysis of DEHP. Measurement of the microsomal marker, glucose 6-phosphatase, and the mitochondrial marker,
succinic dehydrogenase
, revealed that DEHP-hydrolytic activity was associated with microsomes and the 100,000g supernatant fraction, whereas DEHP oxidation was associated only with microsomes.
...
PMID:Metabolism of di-2-ethylhexyl phthalate by subcellular fractions from rainbow trout liver. 1 73
A method is described for the preparation of spheroplasts in high yield from Schizosaccharomyces pombe, by treating cells grown in the presence of glucose and deoxyglucose with snail digestive enzymes. Gentle disruption of such spheroplasts yielded homogenates, from which marker enzymes for nuclei (NAD pyrophosphorylase) and mitochondria (cytochrome c oxidase activity and spectroscopically-detectable cytochromes a + a3) could be quantitatively sedimented by low-speed centrifugation. In contrast to previous findings with Saccharomyces carlsbergensis, cytochrome c oxidase and another mitochondrial enzyme,
succinate dehydrogenase
, were completely sedimentable by zonal centrifugation in sucrose gradients in the presence of either 2 mM-MgCl2 or 0-4 mM-EDTA. Mitochondria were apparently smaller and of lower buoyant density in gradients containing EDTA. The bulk of the total units of malate dehydrogenase and NADH; cytochrome c oxidoreductase sedimented with mitochondria, whereas
NADPH
: cytochrome c oxidoreductase was located in fractions containing no mitochondria. The distributions of mitochondrial enzymes were heterogeneous in populations of mitochondria separated on the basis of size or density. The possible origins of mitochondrial heterogeneity in extracts of S. pombe are discussed with special reference to changes in the enzyme activities of cells during the cell cycle.
...
PMID:Fractionation by differential and zonal centrifugation of spheroplasts prepared from a glucose-repressed fission yeast Schizosaccharomyces pombe 972h-. 18 Feb 35
It is shown that human embryonic cells transformed by Rous sarcoma virus (stable cell line 23) and those transformed by polyoma virus (stable cell line P-2) are morphologically distinguished from the normal human embryonic cells. The mitotic activity of P-2 cells was 51% and the mitotic activity of 23 cells was 48%. While the mitosis activity of human embryo fibroblast was 28%. The duration of the mitosis of P-2 cells was 20 hours and that of 23 cells was 18 hr. The duration of the mitotic cycle of human embryo fibroblast was 18 hr. The G1 periods lasted 6 hours for both the cell lines; the S period of P-2 cells lasted 8 hr and the S period of 23 cells was 6 hr. Both the cell lines had a high content of RNA, DNA, protein bound SH-groups, and a high activity of acid phosphatase, acid RNAase and glucose-6-phosphatase. The content of glycogen, and acidic mucopolysaccharides, the activity of
NADPH
-tetrazolium reductase,
succinic dehydrogenase
of both the lines were the same as in normal human cells.
...
PMID:Morphological and histochemical properties of human embryonic cells transformed by Rous and polyoma viruses. 19 87
Mycotoxic porcine nephropathy was induced by p.o. administration of crystalline ochratoxin A for periods of 5 days, 3 months and 2 years. Enzyme activities of the renal tissue were studied histochemically. These were NADH-tetrazolium reductase,
NADPH
-tetrazolium reductase, lactate dehydrogenase, isocitrate dehydrogenase,
succinate dehydrogenase
, glucose-6-phosphate dehydrogenase, alpha-glycerophosphate dehydrogenase, unspecific acid phosphatase and unspecific alkaline phosphatase. The activity of NADH-tetrazolium reductase and
succinate dehydrogenase
was reduced in the proximal tubule of all nephrons after 5 days ochratoxin A exposure and remained reduced after 3 months and 2 years exposure. The effect of ochratoxin A on these enzymes would appear to cause the impairment of proximal tubular function and the morphological changes observed in the proximal tubule in ochratoxin A-induced mycotoxic porcine nephropathy. The localization of alterations in enzyme activity corresponds to the localization of ochratoxin A previously demonstrated in the kidney. The activities of
NADPH
-tetrazolium reductase, lactate dehydrogenase, glucose-6-phosphate dehydrogenase and unspecific alkaline phosphatase were reduced focally corresponding to the areas with focal tubular atrophy and the degree of reduction was roughly parallel to the degree of atrophy.
...
PMID:Ochratoxin A-induced mycotoxic porcine nephropathy: alterations in enzyme activity in tubular cells. 47 26
In a boy aged 8 years suffering from chronic granulomatosis of childhood necrotizing pneumonie and small pulmonary tuberculoid granulomas containing filaments of moulds were found at autopsy. Necrotizing leucocytic granulomas were present in the liver, spleen and the lymph nodes. All the organs showed aggregates of histiocytes containing yellowish cytoplasmic deposits of lipogment surrounded by a high acid phosphatase activity. The NBT-reduction leucocytic tests was repeatedly negative in vivo. The activities of NADH- and
NADPH
-tetrazolium reductase and
succinate dehydrogenase
in the tissues were histochemically normal.
...
PMID:[Chronic granulomatosis in childhood]. 61 26
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.
...
PMID:Methodological aspects of the histochemical localization and activity of some cerebellar dehydrogenases. 66 87
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.
...
PMID:Histochemical localization of enzymes in the normal rat gastric mucosa using the technique of the semipermeable membranes and the other methods. 82 7
A system is described which permits the separation of isolated hepatocytes and isolated rat liver nuclei belonging to different ploidy classes by velocity sedimentation at unit gravity. The problem of obtaining single cells suspensions is discussed and preparations were obtained that contained 96% single hepatocytes. By improving the sedimentation method, it took 2.5 h to separate rat liver nuclei on sucrose gradients into diploid and tetraploid ploidy classes. Recoveries were generally over 95%. The diploid band was 99% pure. DNA and protein content of the ploidy classes were measured. After partial hepatectomy and [3H]thymidine injection it was found that the label moved largely into the tetraploid compartment. Isolated hepatocytes were fractionated in 1 h on Ficoll gradients. Erythrocytes were separated from small nucleated cells and the population of hepatocytes was clearly separated from these two cell populations. Diploid hepatocytes were 80% and tetraploid hepatocytes were 99% pure. Viability was about 80% after fractionation. The gene dosage of
NADPH
cytochrome c reductase,
succinate dehydrogenase
and lactate dehydrogenase was estimated in diploid and tetraploid hepatocytes. Gene dosage was equal in diploid and tetraploid hepatocytes for
succinate dehydrogenase
and
NADPH
cytochrome c reductase. It is suggested, after correcting for non-viable tetraploid hepatocytes, that the gene dosage of lactate dehydrogenase was significantly lower in diploid than in tetraploid hepatocytes.
...
PMID:Separation of intact rat hepatocytes and rat liver nuclei into ploidy classes by velocity sedimentation at unit gravity. 99 69
In vitro alterations induced by a 10 micrograms/ml and 50 micrograms/ml dose each of thiophenate and fenbendazole on the absorptive surfaces of Haemonchus contortus (Nematoda: Trichostrongylidae) were studied. The most significant changes were induced in the gut epithelium. Alkaline phosphatase and adenosine triphosphatase activities were decreased,
succinic dehydrogenase
activity was increased, while acid phosphatase and glucose-6-phosphatase were completely lost from the intestinal epithelium after treatment with either of the drugs. A stimulatory effect of these two anthelmintics was observe on lactic dehydrogenase and reduced nicotinamide adenine dinucleotide diaphorase distribution. Thiophenate caused an increase in the activities of glutamate dehydrogenase (GDH), glucose-6-phosphate dehydrogenase (G-6-PD) and nonspecific esterases and a decrease in reduced nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-D) activity. Fenbendazole treatment led to the inhibition of GDH, while G-6-PD,
NADPH
-D, cytochrome oxidase, monoamine oxidase and nonspecific esterase activity remained unaltered in the epithelium.
...
PMID:Histoenzymic effects of thiophenate and fenbendazole on the absorptive surfaces of Haemonchus contortus. 133 82
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