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)

The effects of N-substituted tricyanovinylamines on oxidative phosphorylation as well as on glutathione and total SH group concentrations in rat liver mitochondria was studied. The N-TCVA derivatives studied (N-cyclohexyl; N-isobutyl; N-benzyl; N-phenyl; N-4-Br-phenyl; N-3-nitrophenyl) had an uncoupling effection on the oxidative phosphorylation. They stimulated the respiration of mitochondria and influenced their membrane potential. In their property as SH agents, the N-TCVA derivatives reduced the level of TSH groups of the mitochondria present in concentrations of 2 mumol/mg protein. The activity of succinate dehydrogenase was decreased by N-TCVA by 13%. N-TCVA derivatives changed the redox state of glutathione in mitochondria. This effect was observed at the concentration 0.3 mumol/mg protein. The results obtained in the present study support the view that the glutathione status is more sensitive than the total level of SH groups to incubation of mitochondria with SH agents such as N-TCVA derivatives.
Gen Physiol Biophys 1991 Aug
PMID:Effects of N-tricyanovinylamines on oxidative phosphorylation and level of SH-groups in rat liver mitochondria. 176 17

The transcription of the polycistronic puf operon which encodes pigment binding proteins of the reaction center and light-harvesting complex I of Rhodobacter capsulatus is regulated by the oxygen tension in the culture. A DNA sequence upstream of the puf transcriptional start was identified as a protein binding site. A DNA fragment carrying this DNA sequence participated in the formation of two DNA-protein complexes. The relative amounts of the two complexes were dependent on the oxygen tension in cultures from which the cytosolic fraction used for the in vitro binding studies was isolated. A single base pair transition within the protein binding site affected the oxygen-dependent expression of puf in vivo and the formation of DNA-protein complexes in vitro. The data suggest that the formation of specific DNA-protein complexes is involved in the oxygen-dependent regulation of the puf promoter. A DNA fragment containing the promoter region of the puc operon that encodes proteins of the light-harvesting complex II acted as a competitor for the formation of the DNA-protein complexes with the puf-specific fragment, indicating coregulation of the two operons.
Mol Gen Genet 1991 Apr
PMID:A DNA sequence upstream of the puf operon of Rhodobacter capsulatus is involved in its oxygen-dependent regulation and functions as a protein binding site. 203 11

Administration of different doses of L-thyroxine (T4) and triiodo-L-thyronine (T3) in vivo in G. carnosus stimulated the activities of cytochrome oxidase, alpha-glycerophosphate dehydrogenase (alpha-GPDH), succinate dehydrogenase (SDH), and Mg2+ adenosine triphosphatase (Mg2+ ATPase) and inhibited the activity of malate dehydrogenase (MDH). While a low dose of thiouracil administration produced a stimulatory effect on cytochrome oxidase and alpha-GPDH activities, a higher dose of thiouracil significantly inhibited the activities of cytochrome oxidase, alpha-GPDH, SDH, Mg2+ ATPase, and MDH. Injection of T4 or T3 into thiouracil-treated animals significantly restored the stimulatory effect of thyroid hormones on oxidative enzyme activities. It is suggested that thyroid hormones in vivo increase and that thiouracil decreases the oxidative capacity of hepatic mitochondria of G. carnosus.
Gen Comp Endocrinol 1990 Aug
PMID:Stimulation of oxidative metabolism by thyroid hormones in an apodan amphibian, Gegenophis carnosus (Beddome). 216 65

The outer membrane of Campylobacter coli, C. jejuni and C. fetus cell envelopes appeared as three fractions after sucrose gradient centrifugation. Each outer membrane fraction was contaminated with succinate dehydrogenase activity from the cytoplasmic membrane fraction. Similarly the inner membrane fraction was contaminated with 2-ketodeoxyoctonate and outer membrane proteins including the porin(s). The separation of these two membranes was not facilitated by variations in lysozyme treatment, cell age, presence or absence of flagella, or longer lipopolysaccharide chain length. Sodium lauroyl sarcosinate extraction resulted in an outer membrane fraction which contained some inner membrane contamination and produced multiple bands upon sucrose gradient centrifugation. Triton X-100 extraction removed the inner membrane from the outer membrane and Triton X-100/EDTA treatment extracted lipopolysaccharide-rich regions of the outer membrane which contained almost exclusively the Campylobacter porin(s). These data indicated that the inner and outer membranes of the Campylobacter cell envelope were very difficult to separate, possibly because of extensive fusions between these two membranes.
J Gen Microbiol 1988 Nov
PMID:Comparison of methods used to separate the inner and outer membranes of cell envelopes of Campylobacter spp. 247 28

Thyroidectomy and castration in Calotes versicolor significantly decreased the activities of hepatic mitochondrial cytochrome oxidase, alpha-glycerophosphate dehydrogenase (alpha-GPDH), and succinate dehydrogenase (SDH) when compared to sham-operated controls. Administration of thyroid hormones in thyroidectomized lizards and testosterone in castrated specimens stimulated the activities of all three enzymes studied. Chloramphenicol, when injected with thyroxine prevented the hormone-stimulated activities of cytochrome oxidase and SDH, while actinomycin D and chloramphenicol, when administered along with testosterone propionate (low dose) prevented the testosterone-stimulated activities of cytochrome oxidase and alpha-GPDH.
Gen Comp Endocrinol 1988 Mar
PMID:Influence of thyroid hormones and testosterone on the activities of hepatic mitochondrial enzymes in the Indian garden lizard, Calotes versicolor. 283 60

In vivo administration of L-thyroxine (L-T4) in Anabas testudineus, while significantly stimulated the activities of cytochrome c oxidase and alpha-glycerophosphate dehydrogenase (alpha-GPDH), inhibited glucose-6-phosphate dehydrogenase (G-6-PDH), cytosolic and mitochondrial malate dehydrogenase (cyt. MDH; mit. MDH), and Mg2+ DNP-dependent adenosine triphosphatase (Mg2+ ATPase) activities. The activities of lactate dehydrogenase (LDH), succinate dehydrogenase (SDH), and catalase remained unaltered after L-T4 treatment. Administration of protein synthesis inhibitors such as actinomycin D, while significantly inhibited cytochrome oxidase, alpha-GPDH, catalase, SDH, and Mg2+ ATPase activities, did not change LDH, cyt. MDH, and mit. MDH activities. Chloramphenicol injection significantly stimulated cytochrome oxidase, alpha-GPDH, and G-6-PDH activities. Simultaneous injections of actinomycin D or chloramphenicol with 3,5,3'-triiodo-L-thyronine (L-T3) or L-T4 prevented the effects of thyroid hormones on enzyme activities, when compared to the respective controls.
Gen Comp Endocrinol 1989 Jan
PMID:Oxidative metabolism in a teleost, Anabas testudineus Bloch: effect of thyroid hormones on hepatic enzyme activities. 292 Sep 3

Growth of Mycobacterium phlei under low oxygen tension resulted in specific activities two to twenty times lower for formate dehydrogenase, malate dehydrogenase, beta-hydroxybutyrate dehydrogenase, lactate oxidase and NADH dehydrogenase than when cultures were grown under high aeration. An increase in fumarate reductase and succinate dehydrogenase occurred with M. phlei grown under low oxygen tension. Malate: vitamin K dehydrogenase and glucose-6-phosphate dehydrogenase activity were not significantly affected by the oxygen tension used to grow the bacteria, and neither culture contained a lactate dehydrogenase. With growth of M. phlei in conditions of low oxygen tension, cytochrome a was not detected, but cytochrome b was prominent in membranes and cytochrome c was present in the soluble fraction.
J Gen Microbiol 1988 Jan
PMID:Influence of oxygen tension on the respiratory activity of Mycobacterium phlei. 318 14

A transcript analysis of the citrate synthase and succinate dehydrogenase genes (gltA-sdhCDAB) of Escherichia coli was done by nuclease S1 mapping. Evidence was obtained for two monocistronic gltA transcripts extending anti-clockwise, to a common terminus, from independent promoters with start points 196 bp (major) and 299 bp (minor) upstream of the gltA coding region. Evidence was also obtained for two polycistronic sdh transcripts, sdhCDAB (minor) and sdhDAB (major), extending clockwise, from sites 219 bp upstream of sdhC and 1455 bp upstream of sdhD (i.e. within sdhC), to a common terminus. The synthesis of all of the transcripts was repressed by growth in the presence of glucose, and this is consistent with the well-established fact that both enzymes are subject to catabolite repression. Sequences resembling known binding sites for the cAMP-CRP (cyclic AMP-cyclicAMP receptor protein) complex occur in the vicinity of each promoter suggesting that they are activated by the cAMP-CRP complex.
J Gen Microbiol 1986 Dec
PMID:Transcript analysis of the citrate synthase and succinate dehydrogenase genes of Escherichia coli K12. 330 32

Histochemical assays, hormonal quantitation, and steroid biosynthetic studies were carried out with adrenal glands obtained from four stranded whales of two different species (Kogia breviceps and Mesoplodon europaeus), and selected comparisons were made with the results of similar studies of adrenals from terrestrial mammals (man, beef, rat). Histochemical chemical assays of the whale glands for succinic dehydrogenase activity (SDA) showed an intense SDA-positive reaction in the peripheral cortex, and an SDA-negative central medulla, a pattern similar to that found in terrestrial mammals; the whale adrenals, however, demonstrated a markedly pseudolobulated appearance because of a festooned corticomedullary junction. On radioimmunoassay of preformed cortical steroid hormones, corticosterone (B) exceeded cortisol (F) levels by a factor of 3 in the whale adrenals and aldosterone (Aldo) concentrations were 20-100 times lower than in the terrestrial mammals studied. HPLC determinations of preformed medullary catecholamines showed that, contrary to the findings in the terrestrial mammals studied, norepinephrine predominated over epinephrine and the levels of dopamine were much higher in the whale adrenals. In vitro, surviving sections of whale adrenals elaborated B from endogenous substrates, but not F or Aldo. Incubations of subcellular fractions of the whale adrenals with 14C-labeled precursors resulted in the isolation of several steroid intermediates (pregnenolone, progesterone, deoxycorticosterone) as well as the glucocorticoid end-product B, but again without evidence of the formation of either F or Aldo. In keeping with studies in terrestrial mammals, the enzymatic reactions involved in the conversion of [14C]cholesterol to B occurred under aerobic conditions, required the presence of an exogenous NADPH-generating system, and had identical subcellular localization in the whale adrenals. The process of steroid biosynthesis thus appears generally similar in aquatic and terrestrial mammals. It is possible that some of the unusual findings in the whale adrenals studies here may be related to the profound stress of stranding experienced by these marine mammals.
Gen Comp Endocrinol 1987 Nov
PMID:The adrenal gland of stranded whales (Kogia breviceps and Mesoplodon europaeus): morphology, hormonal contents, and biosynthesis of corticosteroids. 342 60

The genes encoding both subunits of the succinyl-CoA synthetase of Escherichia coli have been identified as distal genes of the suc operon, which also encodes the dehydrogenase (Elo; sucA) and succinyltransferase (E2o; sucB) components of the 2-oxoglutarate dehydrogenase complex. The newly defined genes express polypeptides of 41 kDa (sucC) and 31 kDa (sucD), corresponding to the beta and alpha subunits of succinyl-CoA synthetase, respectively. The genes are thus located at 16.8 min in the E. coli linkage map, together with the citrate synthase (gltA) and succinate dehydrogenase (sdh) genes, in a cluster of nine citric acid cycle genes: gltA-sdhCDAB-sucABCD. Four deletion strains lacking all of these citric acid cycle enzymes were characterized. The succinyl-CoA synthetase activities of strains harbouring plasmids containing the sucC and sucD genes were amplified some fourfold. Further enzymological studies indicated that expression of succinyl-CoA synthetase is coordinately regulated with 2-oxoglutarate dehydrogenase.
J Gen Microbiol 1986 Jun
PMID:Cloning and expression of the succinyl-CoA synthetase genes of Escherichia coli K12. 354 12


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