Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P20020 (adenosine triphosphatase)
 3,299 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.
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PMID:Effect of colicin K on a membrane-associated, energy-linked function. 0 29

A method is presented that can be used to perform histochemical and morphometric analyses on the same muscle fiber. Freshly dissected fibers from medial gastrocnemius muscle of adult guinea pig were kept at a resting length and rapidly frozen. Serial frozen cross-sections were cut and reacted for myofibrillar adenosine triphosphatase and succinic dehydrogenase. The adjacent section, while still frozen, was immersed into 20 degrees C glutaraldehyde fixative to which EGTA was added to minimize artifactious contraction. The fixed section was processed for electron microscopy and the section rotated before thin sectioning to give longitudinal sections enabling study of sarcomeres. Ultrastructure was well-preserved despite slight disorganization of the contractile filaments and some vesiculation of the sarcoplasmic reticulum. The Z line width was measured and the mitochondrial volume fraction estimated by point counting morphometry from 89 fibers. The fibers with dark myofibrillar adenosine triphosphatase staining have Z widths of 547 +/- 165 A (n=69) and thoshosphatase staining have Z widths of 547 +/- 165 A (n=69) and those with light stain have 1023 +/- 113 A (n=20). The density of the succinic dehydrogenase reaction product in the fibers was divided into dark and light and the mitochondrial volume fractions were foud to be 4.3 +/- 2.1% (n=52) and 1.0 +/- 1.1% (n=37), respectively.
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PMID:Retrieval of cryostat section for comparison of histochemistry and quantitative electron microscopy in a muscle fiber. 7 99

Exposure of male rats to parathion (2.6 mg/kg), lindane (17.6 mg/kg), or their combination through oral intubation daily for a period of 90 days produced histological and biochemical alterations in the liver and testis. The focal necrosis of the liver, although observed in all the treatments, was very prominent in the animals exposed to lindane alone. The kidney and epididymis, however, did not show any significant histological lesions. The activity of acetylcholine esterase in blood and brain decreased markedly, whereas that of succinic dehydrogenase, adenosine triphosphatase, and the alkaline and acid phosphate in liver and testis showed significant alterations for all three treatments.
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PMID:Comparative response of male rats to parathion and lindane: histopathological and biochemical studies. 9 96

In the gastrocnemius muscle of cat and rat, staining for oxidative enzymes differentiated three fiber types (A,B,C) and staining for adenosine triphosphate at pH 9.4 differentiated two fiber types (I, II) with a reliability of 90% and 98%, respectively. In cat 96% and in rat 90% of the fibers were typed identically after staining for nicotinamide adenine dinucleotidelinked lactic dehydrogenase (LDH) and succinic dehydrogenase (SDH). When differentiated by staining for LDH, A and B fibers were of type I. IN RAT, 80-90% OF ALL FIBERS WERE OF TYPE 22, COMPPRISING A, B and C fibers. Type I fibers stained for LDH intensely as did C fibers of type II, but stained intermediately for SDH. The degree of staining was measured by photometry. When fibers were stained for LDH, histograms of density showed three peaks corresponding to A, B and C fibers in cat, but only two peaks corresponding to A and C fibers in rat, In cat and rat, the densities of A, B and C fibers belonged to different populations. In soleus muscle of cat and rat stained for LDH, menadione-linked alpha-glycerophosphate dehydrogenase and adenosine triphosphatase at pH 9.4, the degree of staining differed from thatin any type of fiber in gastrocnemius muscle
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PMID:Histochemical fiber typing and staining intensity in cat and rat muscles. 12 97

A histochemical study of the effect of ischaemia on rat kidneys showed that changes were demonstrable in adenosine triphosphatase, alkaline phosphatase and succinic dehydrogenase within 2 h. Further changes occurred with increasing time. The activity of acid phosphatase was little affected up to 24 h although at this time there was marked tubular disruption. Paraffin embedded H and E sections also showed marked changes within 2 h. Enzyme histochemical and histological changes in kidneys taken at varying periods after the death of the animal showed very similar changes to those in ischaemic kidneys. Differences were mainly in the rate and extent of the changes.
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PMID:A comparative enzyme histochemical and histological study of the effect of ischaemia and post mortem change on rat kidneys. 12 48

1. The uptakes of Pi and serine by whole cells of mutant strains of Escherichia coli K12, grown under both aerobic and anaerobic conditions, were studied. 2. Uptake by aerobic cells was low in a ubiquinone-less mutant but normal in two mutant strains unable to couple phosphorylation to electron transport. 3. One of these uncoupled strains, carrying the unc-405 allele, does not form a membrane-bound Mg2+-stimulated adenosine triphosphatase aggregate, and it is concluded that the Mg2+-stimulated adenosine triphosphatase does not serve a structural role in the aerobic active transport of Pi or serine. 4. The other uncoupled strain, in which aerobic uptake is unaffected, carries a mutation in the uncB gene, thus distinguishing this gene from the etc gene, previously shown to be concerned with the coupling of electron transport to active transport. 5. The uptakes of Pi and serine by anaerobic cells were normal in the ubiquinone-less mutant, but defective in both the uncoupled strains. 6. The uptake of Pi and serine by anaerobic cells of the uncB mutant could be increased by the addition of fumarate to the uptake medium. The unc-405 mutant, however, required the addition of fumarate for growth and for uptake. 7. The uncB mutant, unlike the unc-405 mutant, is able to grow anaerobically in a minimal medium with glucose as sole source of carbon. Similarly a strain carrying a mutation in the frd gene, which is the structural gene for the enzyme fumarate reductase, is able to grow anaerobically in a glucose-minimal medium. However, a mutant strain carrying mutations in both the uncB and frd genes resembles the unc-405 mutant in not being able to grow under these conditions.
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PMID:Metabolite transport in mutants of Escherichia coli K12 defective in electron transport and coupled phosphorylation. 12 86

A particulate subcellular fraction from Escherichia coli K-12 induced in anaerobic sn-glycerol 3-phosphate (G3P) dehydrogenase and fumarate reductase can catalyze under anaerobic conditions the transfer of hydrogens from G3P to fumarate, with attendant generation of high-energy phosphate. The phsophorylation process is more sensitive than the transhydrogenation process to inhibition by the detergent Triton X-100. The same is true with respect to sensitivity to sodium azide, carbonyl cyanide m-chlorophenylhydrazone and N,N'-dicyclohexylcarbodiimide. Such a preparation derived from cells with beta-galactoside permease can accumulate thiomethyl beta-D-galactoside anaerobically, and the accumulation can be stimulated twofold by adding G3P and fumarate. Mutants lacking the membrane-associated Mg2+-dependent adenosine triphosphatase cannot grow anaerobically on glycerol with fumarate as the hydrogen acceptor, although they can grow aerobically on glycerol alone.
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PMID:Anaerobic energy-yielding reaction associated with transhydrogenation from glycerol 3-phosphate to fumarate by an Escherichia coli system. 12 85

Muscle biopsies were taken from the vastus lateralis of 12 males: 5 control subjects, 4 power lifters and 3 distance runners. Three fiber "types" were distinguished by comparing serial sections for alkaline myofibrillar adenosine triphosphatase (ATPase) and succinic dehydrogenase (SDH) activities: 1. high ATPase and low SDH; fast-twitch-glycolytic (FG). 2. High ATPase and high SDH; fast-twitch-oxidative-glycolytic (FOG). 3. Low ATPase and high SDH; slow-twitch-oxidative (SO). In some cases the distinction between the FOG and FG classess was not clear and a group termed "transitional" was employed. A variation in percentage of fiber types and fiber area was found among individuals. The percentage of SO fibers varied from 19.6-60.1% within all 3 groups, with a mean of 40.5%. In the control group approximately 75% of the fibers were oxidative (FOG + SO). The major characteristics of the lifters were a decrease in the percentage of FOG fibers and a hypertrophy of FOG and FG fibers. The distance runners had a high percentage of oxidative fibers with few FG fibers. It is suggested that the fast-twitch fibers are mainly involved in the adaptation of muscle to exercise since the percentage of SO fibers varies greatly among individuals within and between the 3 groups studied.
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PMID:Human muscle fiber types in power lifters, distance runners and untrained subjects. 13 33

The physiological and histochemical effects of PGF2alpha on isolated rabbit hearts were examined. The results showed a positive inotropic effect. The coronary flow increased. From the histochemical studies, adenosine triphosphatase (ATP-ase) and succinic dehydrogenase activities were increased while that of alkaline phosphatase was decreased. Glycogen granules were depleted. These findings were discussed on a histophysiological basis.
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PMID:Histophysiological studies of prostaglandin F2alpha on isolated organs. I. Effect of prostaglandin F2alpha on the heart. 13 64

In the normal and randomly reinnervated plantaris muscle of rat staining for succinic dehydrogenase (SDH) activity differentiates three fiber types (A, B and C), staining for myofibrillar adenosine triphosphatase (ATPase) differentiates three fiber types (alpha, beta and alpha beta). Here we present our finding type A corresponds to alpha beta fibers, B to beta or alpha beta, C to alpha or alpha beta. In normal soleus muscle both classifications were found to be compatible and B fibers correspond to beta and C to alpha fibers. An exception is the small percent of alpha beta fibers which correspond to B type. In randomly reinnervated soleus muscle changes in ATPase activity are not followed by changes in SDH staining and B fibers correspond to alpha, beta or alpha beta types.
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PMID:Classification of muscle fiber types based on succinic dehydrogenase and myofibrillar ATPase reactions in normal and randomly reinnervated rat skeletal muscles. 14 Aug 39


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