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 fragment of DNA (3.1 kilobases [kb]) from a ColE1 Escherichia coli DNA hybrid plasmid containing the bacterial citrate synthase gene (gltA) was subcloned in both orientations into phage lambda vectors by in vitro recombination. The resulting phages were able to transduce gltA and, as prophages, complemented the lesion of a gltA mutant, showing that a functional gltA gene is contained in the 3.1-kb fragment. The segment of E. coli DNA cloned in these lambda gltA phages was extended in vivo by prophage integration and aberrant excision in the gltA region. Plaque-forming derivatives, carrying up to three additional tricarboxylic acid cycle genes, succinate dehydrogenase (sdh), 2-oxoglutarate dehydrogenase (sucA), and dihydrolipoamide succinyltransferase (sucB), were isolated and characterized by their transducing and complementing activities with corresponding mutants, and the order of the genes was confirmed as gltA-sdh-sucA-sucB. Physical maps of a variety of the transducing phages showed that the four tricarboxylic acid cycle genes are contained in a 12.8-kb segment of bacterial DNA. The four gene products, plus a possible succinate dehydrogenase small subunit, were identified in postinfection labeling studies, and the polarities of gene expression were defined as counterclockwise for gltA and clockwise for sdh, sucA, and sucB, relative to the E. coli linkage map.
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PMID:Molecular cloning of four tricarboxylic acid cyclic genes of Escherichia coli. 628 1

The nucleotide sequence of a 3614 base-pair segment of DNA containing the sdhA gene, encoding the flavoprotein subunit of succinate dehydrogenase of Escherichia coli, and two genes sdhC and sdhD, encoding small hydrophobic subunits, has been determined. Together with the iron-sulphur protein gene (sdhB) these genes form an operon (sdhCDAB) situated between the citrate synthase gene (gltA) and the 2-oxoglutarate dehydrogenase complex genes (sucAB): gltA-sdhCDAB-sucAB. Transcription of the gltA and sdhCDAB gene appears to diverge from a single intergenic region that contains two pairs of potential promoter sequences and two putative CRP (cyclic AMP receptor protein)-binding sites. The sdhA structural gene comprises 1761 base-pairs (587 codons, excluding the initiation codon, AUG) and it encodes a polypeptide of Mr 64268 that is strikingly homologous with the flavoprotein subunit of fumarate reductase (frdA gene product). The FAD-binding region, including the histidine residue at the FAD-attachment site, has been identified by its homology with other flavoproteins and with the flavopeptide of the bovine heart mitochondrial succinate dehydrogenase. Potential active-site cysteine and histidine residues have also been indicated by the comparisons. The sdhC (384 base-pairs) and sdhD (342 base-pairs) structural genes encode two strongly hydrophobic proteins of Mr 14167 and 12792 respectively. These proteins resemble in size and composition, but not sequence, the membrane anchor proteins of fumarate reductase (the frdC and frdD gene products).
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PMID:Nucleotide sequence encoding the flavoprotein and hydrophobic subunits of the succinate dehydrogenase of Escherichia coli. 638 59

The nucleotide sequence of a 961 base-pair segment of DNA containing the sdhB gene, which encodes the iron-sulphur protein subunit of the E. coli succinate dehydrogenase, has been determined. The sdhB structural gene comprises 711 base pairs (237 codons, excluding the translational initiator and terminator). It is separated by a 15 base-pair intergenic region from the preceding flavoprotein gene (sdhA) and is the distal gene of an operon that also includes genes (sdhC and D) encoding two hydrophobic subunits, sdhCDAB. The distal end of the sdh operon is linked to the 2-oxoglutarate dehydrogenase gene (sucA) by a complex region of dyad symmetry that is homologous with several potential intercistronic regulatory elements or transcriptional attenuators. The sdhB structural gene encodes a polypeptide of Mr26637 that is strikingly homologous with the iron-sulphur protein subunit of fumarate reductase (38% identity, increasing to 58% when conservative changes are included). Both subunits contain 11 cysteine residues, 10 being conserved in three clusters resembling those found in ferredoxins. This work completes the sequence of a 9897 base-pair segment of DNA containing seven tricarboxylic acid cycle genes encoding three enzymes or enzyme complexes, citrate synthase (gltA), succinate dehydrogenase (sdh), and the 2-oxoglutarate dehydrogenase complex (suc), that are organized thus: gltA-sdhCDAB-sucAB.
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PMID:Nucleotide sequence encoding the iron-sulphur protein subunit of the succinate dehydrogenase of Escherichia coli. 638 71

NADH:ubiquinone reductase (complex I) of the mitochondrial inner membrane respiratory chain binds a number of mitochondrial matrix NAD-linked dehydrogenases. These include pyruvate dehydrogenase complex, alpha-ketoglutarate dehydrogenase complex, mitochondrial malate dehydrogenase, and beta-hydroxyacyl-CoA dehydrogenase. No binding was detected between complex I and cytosolic malate dehydrogenase, glutamate dehydrogenase, NAD-isocitrate dehydrogenase, lipoamide dehydrogenase, citrate synthase, or fumarase. The dehydrogenases that bound to complex I did not bind to a preparation of complex II and III, nor did they bind to liposomes. The binding of pyruvate dehydrogenase complex, alpha-ketoglutarate dehydrogenase complex, and mitochondrial malate dehydrogenase to complex I is a saturable process. Based upon the amount of binding observed in these in vitro studies, there is enough inner membrane present in the mitochondria to bind the dehydrogenases in the matrix space. The possible metabolic significance of these interactions is discussed.
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PMID:Complex I binds several mitochondrial NAD-coupled dehydrogenases. 643 16

The ATPase activity (proton ATPase) of rat liver mitochondria was studied 2, 24, 28, 96 and 168 h after acute tetrachloromethane poisoning. It is established that the tetrachloromethane poisoning. It is established that the tetrachloromethane poisoning is accompanied by a considerable activation of mitochondrial H+-ATPase and a decrease of the DNP and Ca+, Na+ and K+ activating influence on it. Maximum changes in the H+-ATPase activity is observed 24 h after poisoning. Changes in the H+-ATPase properties are accompanied by a fall in the alpha-ketoglutarate dehydrogenase and succinate dehydrogenase activities and by disturbance of the liver mitochondria contractile properties. The electrochemical membrane potential of the mitochondria under the effect of tetrachloromethane is supposed to be reduced due to a primary damage of the phospholipid matrix of the coupling membrane and an increase in its proton conductivity.
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PMID:[ATPase activity of rat liver mitochondria in acute tetrachloromethane poisoning]. 646 Mar 65

Rat liver mitochondria, stored with the energy-linked functions preserved or in aging conditions, were used to assay the activity of various enzymes during five days. The preservation of energy-linked functions was monitored by the respiratory control coefficient. ATPase, cytochrome oxidase and NADH dehydrogenase showed increased activity when the energy-linked functions were preserved. In aging conditions, cytochrome oxidase, NADH dehydrogenase and ATPase showed decreased activity. The ATPase activity increased only when mitochondria were stored in the presence of inhibitors of the electron transport chain. The activity of NADH oxidase did not change, and succinate oxidase and succinate dehydrogenase showed a small decrease in their activity. The enzymes of the matrix, alpha-ketoglutarate dehydrogenase, malate dehydrogenase and aspartate aminotransferase showed little decrease in activity under either of the conditions of storage. The total protein content decreased slightly under both conditions of storage. These results show that the activity of the enzymes analysed was maintained at reasonable levels, when the energy-linked functions of isolated mitochondria were preserved.
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PMID:Studies on rat liver mitochondria: 4. Enzyme activities in mitochondria preserved at 0-4 degrees C. 646 13

Considerable variations were found in the in vitro effect of alloxan on mouse liver enzymes associated with the citric acid cycle. The following approximative alloxan concentrations induced 50% inhibition of enzyme activity: 10(-6)M for aconitase, 10(-4)M for NAD-linked isocitrate dehydrogenase, glutamate dehydrogenase, alpha-ketoglutarate dehydrogenase, succinyl-CoA synthetase and fumarase, and 10(-3)M for citrate synthase and NADP-linked isocitrate dehydrogenase. Pyruvate dehydrogenase, succinate dehydrogenase and malate dehydrogenase were not inhibited by 10(-3)M alloxan. The inhibition of aconitase was competitive both when using mouse liver and purified porcine heart enzyme. The Ki values for the purified enzyme in the presence of 5 microM alloxan were 0.22 microM with citrate, 4.0 microM with cis-aconitate and 0.62 microM with isocitrate as substrate. The high sensitivity of aconitase for inhibition by alloxan probably plays a prominent role for the toxic effects of alloxan.
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PMID:Inhibition by alloxan of mitochondrial aconitase and other enzymes associated with the citric acid cycle. 651 May 22

The activity of oxidative enzymes of the Krebs cycle was examined in white rats during hypokinesia. On hypokinesia day 7 the cytosol activity of NAD-dependent isocitrate dehydrogenase (ICDH) increased and that of malic-enzyme decreased. On hypokinesia days 30 and 45 the activity of succinate dehydrogenase (SDH) and alpha-ketoglutarate dehydrogenase (alpha-KGDH) decreased, that of cytoplasmatic malate dehydrogenases (MDH) slightly increased, and that of NADP ICDH declined. On hypokinesia day 60 the total activity of mitochondrial dehydrogenases reduced due to a low protein content of the mitochondrial fraction, whereas the specific activity either remained unchanged (ICDH, NAD MDH, alpha-KGDH) or increased (SDH, NADP MDH). On recovery day 25 only the activity of mitochondrial NAD-dependent malate and isocitrate dehydrogenases returned to normal.
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PMID:[Activity of oxidative enzymes of the tricarboxylic acid cycle in the liver of rats during hypokinesia]. 684 75

The study of 165 rats exposed to 60-day hypokinesia demonstrated a decrease in the quantity of mitochondrial protein and a decline in the activity of mitochondrial forms of NADP-isocitrate dehydrogenase (NADP-ICDH) and NAD-malate dehydrogenase (NAD-MDH), as well as NAD-ICDH, succinate dehydrogenase (SDH) and alpha-ketoglutarate dehydrogenase (alpha-KGDH). The maximum decline in the protein content was seen on day 60, and in the enzyme activity on day 7. As the hypokinetic exposure continued, the activity of mitochondrial NAD-MDH and NADP-ICDH slightly increased. The NADP-MDH activity decreased only at later stages of hypokinesia. The changes in cytoplasmic NAD-MDH, NADP-ICDH and NADP-MDH were less expressed. On day 25 of the recovery period the activity of NAD-ICDH and NADP-ICDH was significantly higher than in the controls, that of mitochondrial NAD-MDH returned to the normal, and the activity of SDH and alpha-KGDH remained noticeably lowered.
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PMID:[Oxidative enzyme activity of the tricarboxylic acid cycle in rat skeletal muscles in hypokinesia]. 717 3

Flux through the tricarboxylic acid cycle was calculated from oxygen consumption in hearts perfused near the physiological work load. Activities of citrate synthase, 2-oxoglutarate dehydrogenase and succinate dehydrogenase were measured in the same hearts. Only the activities of 2-oxoglutarate dehydrogenase correlated with calculated fluxes through the cycle.
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PMID:Tricarboxylic acid cycle flux and enzyme activities in the isolated working rat heart. 734 78


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