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 isolation and partial characterization of subcellular particles from rabbit and rat lung are described. Detailed methods for separating a purified, active mitochondrial fraction are outlined and evaluated in terms of enzymatic, chemical, and morphological criteria. Mitochondrial preparations from rabbit and rat liver were used as comparative indices. The lung mitochondrial fraction was identified by its ability to oxidize succinate with a P/O ratio of 1.7 by a process sensitive to 2,4 dinitrophenol and antimycin A. The adenosine triphosphatase activity of the lung mitochondrial fraction is stimulated by magnesium ions, but this stimulation is not augmented by 2,4 dinitrophenol. In the absence of magnesium ions, the specific activity of the adenosine triphosphatase increases with increasing protein concentration. The presence of lysosomes in the mitochondrial fraction is suggested by acid phosphatase and cathepsin activities and by electron microscope observations.
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PMID:Studies of lung metabolism. I. Isolation and properties of subcellular fractions from rabbit lung. 422 9

The virus of transmissible gastroenteritis produced sprue-like lesions in the small intestines of young pigs. These lesions were characterized by villous shortening, fusing and blunting in the jejunum and ileum. There was decreased height of the brush border and morphologic alteration of the villous epithelial cells from simple columnar to a variable cuboidal type. Accompanying these microscopic lesions were histochemical changes characterized by decreased staining intensity of acid phosphatase, alkaline phosphatase, adenosine triphosphatase, leucine aminopeptidase, succinic dehydrogenase and malic dehydrogenase in the affected intestinal mucosa. The clinical nature of transmissible gastroenteritis in the pig together with the histopathologic and histochemical changes may provide a useful experimental model for obtaining additional basic information on enteric disturbances.
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PMID:Experimental sprue-like small intestinal lesions in pigs. 422 30

An Mg(2+)-dependent and a K(+)-stimulated adenosine triphosphatase were localized by cytochemistry at or near both surfaces of the cytoplasmic membrane of Myxococcus xanthus. An alkaline and an acid phosphatase resided at the external surface of the membrane or in the periplasm. All enzymes could be extracted from partially fixed cells with Mg(2+)-deficient buffers. Suboptimal external phosphate elicited dissociation of adenosine triphosphatase from the membrane but not that of the unspecific phosphatases. The dissociated enzymes migrated into the cytoplasm where they were associated mainly with cytoplasmic aggregates.
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PMID:Cytochemistry of phosphatases in Myxococcus xanthus. 423 39

A light microscopy study on the localization of enzyme activity within atherosclerotic human intracranial arteries was performed on autopsy material obtained within 4 hours of death. The data suggests that the atherosclerotic process first goes through a proliferative phase and then a degenerative phase culminating in the formation of a plaque. In the proliferative phase, smooth muscle cell proliferation has formed a thickened intima. Tetrazolium reductase, adenosine triphosphatase (ATPase) and adenosine monophosphatase (AMPase) activities are present in these cells, while all dehydrogenases and acid phosphatase activities were weak or not present. As the degenerative phase commences, an area of necrosis, lipid and macrophage accumulation is formed on the lumen side of the elastica. This area increases in size until a plaque is formed. Unsaturated polar and nonpolar lipid, cholesterol, alpha-glycerophosphate dehydrogenase, acid phosphatase, and AMPase activities are associated with these areas and in foam cells, which are often found in the thickened intima of the proliferative phase. Tetrazolium reductase and ATPase activities decrease in the thickened intima as the area of necrosis increases in size, while dehydrogenase activity, except that for alpha-glycerophosphate, remains low or not present. Patterns of enzyme alterations for various stages of the disease process in intracranial arteries, the aorta and coronary arteries suggest a similar, if not identical, progression of the atherosclerotic process, irrespective of known differences in the prevalence of atherosclerosis.
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PMID:A histoenzymatic study of human intracranial atherosclerosis. 426 Jul 21

1. The action of beryllium on the following enzymes has been examined: alkaline phosphatase (Escherichia coli and kidney), acid phosphatase, phosphoprotein phosphatase, apyrase (potato), adenosine triphosphatase (liver nuclei, liver mitochondria, brain microsomes), glucose 6-phosphatase, polysaccharide phosphorylases a and b, phosphoglucomutase, hexokinase, phosphoglyceromutase, ribonuclease, A-esterase (rabbit serum), cholinesterase (horse serum), chymotrypsin. Alkaline phosphatase and phosphoglucomutase are inhibited by 1mum-beryllium sulphate whereas the other enzymes are largely unaffected by 1mm-beryllium sulphate. 2. Possible mechanisms for the inhibition of phosphoglucomutase and alkaline phosphatase are discussed.
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PMID:The inhibition of enzymes by beryllium. 428 87

1. The kinetics of inhibition of calf-intestinal alkaline phosphatase by inorganic phosphate, fluorophosphate, inorganic pyrophosphate, beta-glycerophosphate and adenosine 5'-triphosphate in the range pH8-10 were investigated. The reference substrate was 4-methylumbelliferyl phosphate. 2. The inhibitions were ;mixed' in that both K(m) and V were affected, but the competitive element was by far the stronger. 3. In each case the pH profile for the competitive K(i) was similar to the pH profile for K(m). Since the K(m) and K(i) values both change 100-fold over the pH range 8-10, it is concluded that the inhibitors compete with the substrate for the same active site. 4. It was also found that the enzyme preparation hydrolysed fluorophosphate, pyrophosphate and adenosine 5'-triphosphate as readily as it hydrolysed 4-methylumbelliferyl phosphate and beta-glycerophosphate. Each pH-activity curve, however, had a different shape, but with the exception of pyrophosphate the activity approached the same maximum value at high pH. 5. Attempts to separate the phosphomonoesterase and pyrophosphatase activities by column chromatography were not successful, and the results of other experiments listed suggest that the two activities are a property of the same enzyme. 6. The effect of Mg(2+) ions is briefly mentioned: the phosphomonoesterase activity is enhanced whereas the pyrophosphatase and adenosine triphosphatase activities are strongly inhibited in the presence of excess of Mg(2+) ions.
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PMID:Studies on alkaline phosphatase. Inhibition by phosphate derivatives and the substrate specificity. 429 74

Endogenous enzyme activity can be readily and routinely demonstrated in ultrathin, frozen sections for electron microscopy. The procedure employed to obtain the best structural preservation as well as enzyme activity in thin sections involved fixation in glutaraldehyde, embedding in thiolated gelatin or pure gelatin, partial dehydration in glycerol, and sectioning in a cryostat at -35 degrees C with a slightly modified Porter-Blum microtome on which the tissue is maintained at -70 degrees C and the knife at -23 degrees C. Kidney cortex was used as test tissue, but a few other organs were occasionally used. Thin sections were floated on the surface of several incubation media routinely employed for enzyme cytochemistry. Positive, specific reactions were obtained for alkaline phosphatase in kidney brush border, for adenosine triphosphatase in brush border and in basal membranes of distal tubules, for acid phosphatase and esterase in lysosomes, and for NADH diaphorase in mitochondria. Mitochondrial ATPase was sporadically evident only in the distal tubule of the kidney. Localizations of enzyme activity reported by other technical approaches were confirmed and in some cases somewhat improved.
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PMID:Ultrathin frozen sections. II. Demonstration of enzymic activity. 429 6

Staphylococus aureus, ATCC 6538P, was fractionated into protoplast membranes, mesosomal vesicles, periplasm, and cytoplasm. These fractions and the culture fluid were then assayed for various degradative enzyme activities. They were not restricted to a single fraction nor dispersed homogeneously, but were distributed predominantly (on the basis of specific activity) as follows: nuclease in the culture fluid; alkaline phosphatase, 5'-nucleotidase, and acid phosphatase in the periplasm; adenosine triphosphatase in the protoplast membrane; and protease (low levels) in mesosomal vesicles. No significant esterase nor cell wall hydrolytic activity was found in any fraction. S. aureus 80/81 was studied for penicillinase activity after induction with benzyl penicillin; this enzyme was localized in the mesosomal vesicles. Electron microscopy did not reveal any ultrastructural changes associated with secretion of the extracellular fraction. Overall, these studies demonstrate that degradative enzymes are located in several surface compartments and that, therefore, the mesosome does not function as a prototype lysosome in S. aureus.
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PMID:Cellular location of degradative enzymes in Staphylococcus aureus. 437 33

Non-specific and specific phosphatases have been histochemically localized in the tissues of Avitellina lahorea, an intestinal parasite of sheep and goats. Large quantities of acid phosphatase, alkaline phosphatase and adenosine triphosphatase were observed in almost all organs except the parenchyma where there were moderate amounts of acid phosphatase and no alkaline phosphatase; the reproductive ducts contained moderate amounts of alkaline phosphatase. 5-nucleotidase was observed only in the uterus, egg pouches and eggs and glucose-6-phosphatase activity was restricted to the tegument. The probable functions of these moieties at different sites are discussed.
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PMID:Histochemical localization of phosphomonoesterases in Avitellina lahorea Woodland, 1927 (Cestoda: Anoplocephalida). 608 41

The uteri of 8 goats (2 each at pregnancy, estrus, diestrus, and prepubertal periods) were used for histoenzymic localization of alkaline phosphatase (AKP), acid phosphatase (ACP), glucose-6-phosphatase (G6P), and adenosine triphosphatase (ATPase). In the surface and glandular epithelia of endometrium, all the enzymic reactions showed no appreciable change during pregnancy as compared with diestrus, except that the G6P activity was reduced. At estrus, the AKP reaction in the surface as well as glandular epithelia and ATPase in the glandular epithelium did not change, the ACP decreased and G6P increased in both epithelia but ATPase decreased in surface epithelium. Caruncular tissue showed increased AKP and decreased ACP and ATPase reactions at estrus, all being maximum during pregnancy. No specimen showed G6P reaction in the caruncular tissue. In prepubertal uteri, all the enzymes studied were localized in the same locations as in diestrus uteri except that ACP and G6P were not localized in the caruncular tissue. The myometrium of all the samples demonstrated only ATPase.
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PMID:Histoenzymic studies on phosphatases in the uterine wall of the goat (Capra hircus). 609 1


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