Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
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Gene/Protein
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Target Concepts:
Gene/Protein
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Enzyme
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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)
Enzymatic techniques were used to study the metabolism of carbohydrates by ruminal bacteria. A direct relationship was observed between the proportions of acetate and propionate formed and the specific activities of the enzymes which participate in forming these acids. An inverse relationship between butyrate formation and butyrate-forming enzymes was observed. The relative activities of
succinic dehydrogenase
to fumaric reductase,
nicotinamide
adenine dinucleotide-linked glutamic dehydrogenase to
nicotinamide
adenine dinucleotide phosphate-linked glutamic dehydrogenase, and pyridine nucleotide-nonlinked lactic dehydrogenase to pyridine nucleotide-linked lactic dehydrogenase were affected by the level of concentrates in the diet. Lactyl coenzyme A dehydrase activity was below the limits of the assay technique in many samples from the alfalfa hay diet, and increased to relatively high levels when concentrates were fed. It is suggested that the enzymatic method will prove valuable for studying the contributions of individual microorganisms to the overall ruminal metabolism, and, with certain limitations, useful for estimating the relative contributions of alternate pathways.
...
PMID:Enzymatic techniques for the study of pathways of carbohydrate utilization in the rumen. 595 Feb 50
A single administration of chlorophos (trichlorophon) solution (600 mg/kg) (LD50) results in vacuolar distrophy appearing in the white rat liver and is especially pronounced in 2-4 days. Thirty minutes after the poisonous chemical is administered, butyrilcholinesterase (BChE) activity is inhibited by 90%, somewhat later oxidation-reduction enzymes activity decreases and alkaline phosphatase (APh) activity increases. Cytoplasm of hepatocytes is filled with glycogene and nearly deprived of RNA. Owing to the cytophotometric analysis of the enzymatic activity and the stereologic morphometry method, it has been possible to reveal a certain synchronism in the development of distrophic processes, in a decreasing activity of the oxidation-reduction enzymes and in a disturbed synthesis of glycogene and RNA. On the 6th day after chlorophos has been administered,
succinate dehydrogenase
and
nicotinamide
-adenine-dinucleotide-phosphate-diaphorase activity, as well as contents and distribution of RNA in hepatocytes reach their control values. BChE and APh activity does not restore. During the whole experiment there is not any statistically significant change in the volumetric part of the sinusoid capillaries and in the stellate reticuloendotheliocytes. Thus, the main effect of chlorophos action is a specific inhibition of ChE, that results in certain structural changes and in changes of the histoenzymatic parameters of the liver.
...
PMID:[Morpho-functional changes in the liver after exposure to cholinesterase inhibitors]. 619 75
We determined muscle fiber type and capillarity in cremaster muscle samples from rats and hamsters of different ages. Histochemical estimation of oxidative capacity was made from the activity of either
nicotinamide
dinucleotide tetrazolium reductase (NADH-TR) or
succinic dehydrogenase
(
SDH
), and fibers were termed fast or slow from myofibrillar ATPase activity. Fibers were classified as type I (low ATPase, high NADH-TR/
SDH
), type IIa (high ATPase, high
SDH
/NADH-TR), type IIb (high ATPase, low
SDH
/NADH-TR), or type IIc (no acid reversal of ATPase, high NADH-TR). Type IIb fibers accounted for 60-80% of the muscle area in both species at all ages. The principal change with maturation was muscle fiber hypertrophy. Mean cross-sectional fiber area increased from 488 +/- 70 (SE) and 453 +/- 19 micron2 in young hamsters and rats, respectively, to 1,255 +/- 99 and 1,540 +/- 101 micron2 in adults. Capillary density (no. of capillaries/mm2 tissue) paralleled fiber hypertrophy; it decreased significantly with maturation from 684 +/- 60 (SE) to 228 +/- 26/mm2 in hamsters and from 341 +/- 15 to 213 +/- 15/mm2 in rats. In vitro estimates of capillary density are compared with previously obtained in vivo data (31), and sources of error are identified. We conclude that reported differences in microvascular function in the cremaster muscle in vivo during maturation or between species cannot be ascribed to changes in muscle composition.
...
PMID:Capillarity and fiber types in the cremaster muscle of rat and hamster. 622 29
Parietal cells in the luminal segments of mouse gastric glands show high activity of acid-secreting potassium-dependent adenosine triphosphatase (H+, K+-ATPase) and of
nicotinamide
adenine dinucleotide-linked isocitrate dehydrogenase (NAD-ICDHase) and malate dehydrogenase (MDHase) but low activity of
succinate dehydrogenase
(SDHase). This pattern of activity is reversed in the basal segments of the same glands. These results and previous morphological findings support the conclusion that luminal segment parietal cells are much more active in hydrochloric acid secretion than those of the basal segment. The origin of this zonation may be either cellular deterioration with age or some more specific form of regulation of parietal cell metabolism.
...
PMID:Cytochemical evidence for functional zonation of parietal cells within the gastric glands of the mouse. 631 15
A comparison was made of muscle from two locations in both the longissimus and the semitendinous muscles of normal and malignant hyperthermia-susceptible swine. Serial frozen sections were stained for alkali-stable adenosine triphosphatase (ATPase), phosphorylase, and the oxidative enzymes
succinate dehydrogenase
and reduced
nicotinamide
adenine dinucleotide (NADH)-diaphorase. Myofiber types were identified on the basis of these staining reactions. There was no consistent statistically significant difference between muscle from normal and muscle from susceptible swine with any system of fiber classification. This is contrary to several published reports but consistent with physiologic studies which indicate that both oxidative and glycolytic pathways are abnormally active during the onset of malignant hyperthermia.
...
PMID:Histochemical observations on muscle from normal and malignant hyperthermia-susceptible swine. 644 66
The profiles of fiber types in hindlimb muscles from the tree shrew (Tupaia glis), lesser bushbaby (Galago senegalensis), and the slow loris (Nycticebus coucang) were determined using histochemical techniques. Fibers were classified as fast-twitch oxidative-glycolytic (FOG), fast-twitch glycolytic (FG), slow-twitch oxidative (SO), or fast-twitch oxidative (FO), according to reactions for alkaline-stable ATPase, acid-stable ATPase, alpha-glucan phosphorylase, reduced
nicotinamide
adenine dinucleotide diaphorase,
succinate dehydrogenase
, mitochondrial alpha-glycerophosphate dehydrogenase (MaGPDH), and beta-hydroxybutyric dehydrogenase, as well as glycogen staining by the periodic acid-Schiff technique. Prolonged dissection of numerous muscles was carried out on hindlimbs submersed in cold Tyrode's solution; such treatment had no qualitative effect on enzyme staining reactions, but it is not a suitable procedure if one wishes to stain for glycogen. Fast-twitch oxidative (FO) fibers are alkaline-stable ATPase-positive and possess low MalphaGPDH enzyme activity. These fibers have not been reported previously in any hindlimb muscles. No muscles of any species studies were homogeneous with respect to fiber type. Slow loris muscles lacked FG fibers. The majority of the muscles of the slow loris contained numerous SO fibers. The relationship between enzyme activities and locomotor pattern is discussed.
...
PMID:Comparative histochemical study of prosimian primate hindlimb muscles. I. Muscle fiber types. 645 15
We have developed methods for separating the cytoplasmic and outer membranes of vegetative cells of Myxococcus xanthus. The total membrane fraction from ethylenediaminetetraacetic acid-lysozyme-treated cells was resolved into three major fractions by isopycnic density centrifugation. Between 85 and 90% of the
succinate dehydrogenase
and cyanide-sensitive reduced
nicotinamide
adenine dinucleotide oxidase activity was found in the first (I) fraction (rho = 1.221 g/ml) and 80% of the membrane-associated 2-keto-3-deoxyoctonate was found in the third (III) fraction (rho = 1.166 g/ml). The middle (II) fraction (rho = 1.185 g/ml) appeared to be a hybrid membrane fraction and contained roughly 10 to 20% of the activity of the enzyme markers and 2-keto-3-deoxyoctonate. No significant amounts of deoxyribonucleic acid or ribonucleic acid were present in the three isolated fractions, although 26% of the total cellular deoxyribonucleic acid and 3% of the total ribonucleic acid were recovered with the total membrane fraction. Phosphatidylethanolamine made up the bulk (60 to 70%) of the phospholipids in the membrane fractions. However, virtually all of the phosphatidylserine and cardiolipin were found in fraction I. Fraction III appeared to contain elevated amounts of lysophospholipids and contained almost three times the amount of total phospholipid as compared with fraction I. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis resolved approximately 40 polypeptides in the total membrane fraction. Two-thirds of these polypeptides were enriched in fraction I, and the remainder was enriched in fraction III. Fraction II contained a banding pattern similar to the total membrane fraction. Electron microscopy revealed that vegetative cells of M. xanthus possessed an envelope similar to that of other gram-negative bacteria; however, the vesicular appearance of the isolated membranes was somewhat different from those reported for Escherichia coli and Salmonella typhimurium. The atypically low bouyant density of the outer membrane of M. xanthus is discussed with regard to the high phospholipid content of the outer membrane.
...
PMID:Separation and properties of the cytoplasmic and outer membranes of vegetative cells of Myxococcus xanthus. 676 94
14C-labeled bicarbonate was incorporated into trichloroacetic acid-insoluble material by cell suspensions of A. viscosus strain M100 and also into the four-carbon fermentation product, succinate, but not into the three-carbon fermentation product, lactate. The initial step in the conversion of 14C-labeled bicarbonate into both trichloroacetic acid-insoluble material and succinate was catalyzed by the enzyme phosphoenolypyruvate carboxylase, which served to convert the glycolytic intermediate, phosphoenolpyruvate, and bicarbonate to the four-carbon compound, oxalacetate. The metabolic fate of oxalacetate was its conversion to either trichloroacetic acid-insoluble material or succinate. One pathway by which oxalacetate may be metabolized into acid-insoluble material is via its conversion to the biosynthetic precursor aspartate by the action of glutamate aspartate aminotransferase. One source of the alpha-amino group of aspartate was the ammonium ion, which could be incorporated into glutamate, the substrate of the glutamate aspartate aminotransferase reaction, by the action of a reduced
nicotinamide
adenine dinucleotide phosphate-dependent glutamate dehydrogenase whose reducing equivalents could be derived from the
nicotinamide
adenine dinucleotide phosphate-dependent oxidative reactions of the hexose monophosphate pathway catalyzed by glucose 6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase. Alternatively, oxalacetate was converted to the fermentation product, succinate, through the sequential action of malate dehydrogenase, fumarase, and
succinic dehydrogenase
. The resolution and partial purification of phosphoenolpyruvate carboxylase, glutamate aspartate aminotransferase, glutamate dehydrogenase, malate dehydrogenase, fumarase, and
succinic dehydrogenase
are also reported.
...
PMID:Carbon dioxide metabolism by Actinomyces viscosus: pathways for succinate and aspartate production. 676 22
Isolated membranes of the cell wall-less stable protoplast L-form of Proteus mirabilis were characterized by density gradient centrifugation and by assay for their major chemical constituents, proteins, phospholipids and lipopolysacchartide, and for some specific marker enzymes of the cytoplasmic membrane. In most of the analyzed properties the L-form protoplast membrane resembled the bacterial cytoplasmic membrane, with some notable modifications. Considerable amounts of lipopolysaccharide, normally an exclusive constituent of the outer membrane, were found. Furthermore, the L-form membranes contained the functions of the reduced
nicotinamide
adenine dinucleotide oxidase system, of D-lactate dehydrogenase (EC 1.1.1.28) and of
succinate dehydrogenase
(EC 1.3.99.1) at specific activities comparable to, or in some cases considerably higher than, those present in cytoplasmic membranes of the bacterial form. Of two peptidoglycan DD-carboxypeptidase/transpeptidases (EC 3.4.17.8 and EC 2.3.2.10). which are normally present in the cytoplasmic membrane of the bacterial form of P. mirabilis, the membrane of the protoplast L-form contained only one. Electron microscopy of thin sectioned L-form protoplasts showed extensive heterogeneity of membraneous structures. In addition to the single membraneous integument, internal membrane-bounded vesicles and multiple stacks of membranes were present, as the result of unbalanced growth and membrane synthesis in the L-form state.
...
PMID:Membranes of the protoplast L-form of Proteus mirabilis. 700 76
Light and heavy membrane fractions have been isolated by equilibrium sucrose density centrifugation from Rhodopseudomonas capsulata 938 GCM grown aerobically in the dark (chemotrophically) and anaerobically in the light (phototrophically). The densities of the light and heavy fractions from phototrophic cells were 1.1004 to 1.1006 and 1.1478, respectively, and the densities of the light and heavy fractions from chemotrophic cells were 1.0957 to 1.0958 and 1.1315, respectively. Both fractions were active in photochemical and respiratory functions and in electron transport-coupled phosphorylation. The light membrane fraction isolated from chemotrophic cells contained the reaction center and the light-harvesting pigment-protein complex B 870, but not the variable light-harvesting complex B 800-850. A small amount of the complex B 800-850 was present in the light fraction isolated from phototrophically grown cells, but it was not energetically coupled to the photosynthetic apparatus. From inhibitor studies, difference spectroscopy, and measurement of enzyme activities it was tentatively concluded that the light membrane fraction contains only the reduced
nicotinamide
adenine dinucleotide-oxidizing electron transport chain having a KCN-insensitive, low-potential cytochrome c oxidase, whereas the heavy fraction contains additionally the
succinate dehydrogenase
and a high-potential cytochrome b terminal oxidase sensitive to KCN. The light membrane fraction was more labile than the heavy fraction in terms of phosphorylating activity.
...
PMID:Comparative studies of two membrane fractions isolated from chemotrophically and phototrophically grown cells of Rhodopseudomonas capsulata. 720 41
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