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)

Net synthesis of adenosine 5'-triphosphate (ATP) in energy-depleted cells of Escherichia coli was observed when an inwardly directed protonmotive force was artificially imposed. In wild-type cells, ATP synthesis occurred whether the protonmotive force was dominated by the membrane potential (negative inside) or the pH gradient (alkaline inside). Formation of ATP did not occur unless the protonmotive force exceeded a value of 200 mV. Under these conditions, no ATP synthesis was found when cells were exposed to an inhibitor of the membrane-bound Ca2+- and Mg2+- stimulated adenosine triphosphatase (EC 3.6.1.3), dicyclohexylcarbodiimide, or to a proton conductor, carbonylcyanide-p-trifluoromethoxyphenyl-hydrazone. Adenosine triphosphatase-negative mutants failed to show ATP synthesis in response to either a membrane potential or a pH gradient. ATP synthesis driven by a protonmotive force was observed in a cytochrome-deficient mutant. These observations are consistent with the chemiosmotic hypothesis of Mitchell (1961, 1966, 1974).
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PMID:Protonmotive force as the source of energy for adenosine 5'-triphosphate synthesis in Escherichia coli. 0 27

After the repeated injection of sea urchin sperm guanylate cyclase into rabbits, antibodies to the enzyme were formed. These antibodies inhibited the particulate or the Triton-dispersed forms of the sperm enzyme by greater than 97%. The sperm adenylate cyclase, cyclic GMP phosphodiesterase, adenosine triphosphatase, guanosine triphosphatase, and 5'-nucleotidase enzymes were not affected by the antiserum. The antiserum inhibited the Triton-dispersed guanylate cyclase from rat heart, liver, lung, spleen, and kidney but did not inhibit the soluble form of the enzyme from any of these tissues. The inhibition of the Triton-dispersed enzyme in these tissues was partial, however, ranging from 30% (liver) to 70% (heart). These results provide evidence that adenylate cyclase is antigenically different from guanylate cyclase, and that the soluble form of guanylate cyclase is antigenically different from a particulate form of the enzyme in various rat tissues.
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PMID:Sea urchin sperm guanylate cyclase antibody. Cross-reactivity various rat tissue guanylate cyclases. 2 31

1. The specific activity of rat and pig liver nuclear-envelope nucleoside triphosphatase (EC 3.6.1.3) decreases when the system is depleted of RNA. The activity can be restored by adding high concentrations of yeast RNA to the assay medium. 2. Exogenous RNA also increases the activity of the enzyme in control envelopes (not RNA-depleted). The effect appears to be largely specific for poly(A) and poly(G); it is not stimulated by rRNA or tRNA preparations, ribonuclease-hydrolysed RNA, AMP, or double- or single-stranded DNA. 3. Inhibitors of the enzyme, in concentrations at which half-maximal inhibition of the enzyme is achieved, do not affect the percentage stimulation of the enzyme by yeast RNA. 4. The simulation is abolished by the inclusion of 150 mM-KCl or -NaCl in the assay medium, but not by increasing the assay pH to 8.5. 5. The results are discussed in the light of the possible role of the nucleoside triphosphatase in vivo in nucleo-cytoplasmic ribonucleoprotein translocation. 6. It is proposed that poly(G)-stimulated Mg2+-activated adenosine triphosphatase activity should be adopted as an enzymic marker for the nuclear envelope.
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PMID:Ribonucleic acid stimulation of mammalian liver nuclear-envelope nucleoside triphosphatase. A possible enzymic marker for the nuclear envelope. 14 Dec 76

Ultrastructural distribution of adenosine triphosphatase and thiamine pyrophosphatase in synapses of rat's cerebral cortex was studied. Adenosine triphosphatase activity in some synaptic vesicles and mitochondria, on pre- and postsynaptic membranes, as well as in the postsynaptic thickening was established. The reaction specificity was proved by means of some controls: various concentrations of ouabain, NaF, NiCl2, cysteine, substrate free medium and non-specific substrates - cocarboxylase and beta-glycerophosphate. At the thiamine pyrophatase reaction, the enzyme positive product was found on the membrane of some clear synaptic vesicles, on the singl sacs of smooth endoplasmic reticulum in the axon terminal, and bouton cell membrane. Substrate free medium, addition of cystein and substitution of orininal substrate with adenosine triphosphate and beta-glycerophosphate as controls were used. The fine structure localization of both enzymes in synaptic structures suggests their important role in the synaptic function.
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PMID:Cytochemical localization of adenosine triphosphatase and thiamine pyrophosphatase in the synapases of rat's cerebral cortex. 14 1

The present study deals with the distribution of adenosine triphosphatase and 5'-nucleotidase in the various constituents of thoracic ganglia and associated nerve of Periplaneta americana. The localization of both the enzymes in the thoracic ganglia is identical. The neural lamella is devoid of any activity for both the enzymes. The ganglion cells are intensely positive at their borders. The neuronal cell surface and/or glial cell processes which envelope the neurons show intense activity for these enzymes. Adenosine triphosphatase and 5'-nucleotidase are present around "giant fibres" and small axons. The activity appears to confine itself in the sheaths. The cytoplasm and the nuclei of the neurons are devoid of enzymatic activity, whereas the nucleoli are slightly active. The nerves are positive for both the enzymes. The role of these enzymes at different sites has also been discussed.
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PMID:Histochemical studies on the distribution of adenosine triphosphatase and 5'-nucleotidase amongst the constituents of the thoracic ganglia and the associated nerve of Periplaneta americana. 14 3

Seven well differentiated chondrosarcomas of bone have been analyzed by electron microscopy, and the fine structural localization of adenosine triphosphatase and nonspecific alkaline phosphatase has been elucidated. On the basis of the fine structural appearance, two distinct cell types were shown to constitute the tumor tissue: chondrocyte-like cells and large "mitochondria-rich cells". Large, multinucleated cells in the tumor did not seem to correspond to osteoclasts but rather were likely to represent true neoplastic cells. Some chondrocyte-like cells appeared to be binucleated by virtue of deep, groove-like nuclear indentations. Adenosine triphosphatase and alkaline phosphatase were associated with the plasma membrane of both chondrocyte-like and mitochondria-rich cells suggesting that they might be of common origin. Normal chondroblasts and chondrocytes lack histochemically demonstrable adenosine triphosphatase on their plasma membrane. Presence of this enzyme in the tumor cells may indicate that they are histogenetically related to immature non-chondroid matrix forming cells (known to carry the enzymes).
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PMID:Contribution to the knowledge of the fine structure of chondrosarcoma of bone. With a note on the localization of alkaline phosphatase and "ATPase". 15 79

Electron microscopic cytochemistry was used to determine the localization of five phosphatase enzymes-glucose-6-phosphatase, inosine diphosphatase, thiamine pyrophosphatase, acid phosphatase, and adenosine triphosphatase-in control human testes. Glucose-6-phosphatase occurred in the endoplasmic reticulum and nuclear envelope of Sertoli cells, Leydig cells and primitive spermatogonia, but was not observed in more advanced spermatogenic cells. The presence of glucose-6-phosphatase activity paralleled the presence of glycogen in spermatogenic cells, i.e., both occurred in type AL and AD spermatogonia but not in type AP or B spermatogonia or in more advanced spermatogenic cells. Inosine diphosphatase activity was found in the endoplasmic reticulum, nuclear envelope, and Golgi complex of Sertoli cells and all spermatogenic cells except late spermatids. Additionally, inosine diphosphatase activity was localized at the junctions between Sertoli cells and late spermatids, but was not associated with any other plasma membrane. Thiamine pyrophosphatase reaction product was found in the Golgi bodies of Sertoli cells and in spermatogenic cells through immature spermatids. Neither inosine diphosphatase nor thiamine pyrophosphatase was observed in the Golgi bodies of spermatids during acrosomal formation. Acid phosphatase activity was found in lysosomes of spermatogonia, spermatocytes, and spermatids, in lysosomes of Leydig cells, and in lysosomes, lipofuscin bodies, and Golgi cisternae of Sertoli cells. It is thought that Sertoli lysosomes play a role in the phagocytosis of degenerating germ cells; however, the role of spermatogenic or Leydig lysosomes is unknown. Adenosine triphosphatase activity occurred at the interfaces between two spermatogonia, and between Sertoli cells and spermatogonia, but was not observed in the spaces between two Sertoli cells, two spermatocytes, two spermatids, or between Sertoli cells and spermatocytes, or between Sertoli cells and spermatids.
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PMID:The fine structural localization of testicular phosphatases in man: the control testis. 17 58

The acitvities of sodium-potassium-activated adenosine triphosphatase (Na+,K+-activated ATPase) and ouabain-inhibited, sodium-potassium-activated adensoine triphosphatase (Na+,K+-ATPase) in subcellular fractions of guinea-pig and rat vasa deferentia were compared to determine whether the ineffectiveness of ouabain and reduced extracellular potassium in the rat vas deferens observed in the preceding paper occurs because of a relatively low level of Na+,K+-ATPase and/or an insensitivity to ouabain. The results indicate that the specific and total activities of Na+,K+-activated ATPase and Na+,K+-ATPase (i.e., the transport enzyme) in the individual subcellular fractions and in the tissue were higher in the vas deferens of the rat than in the guinea pig. The percentage of inhibition of Na+,K+-activated activity by ouabain (8 x 10(-5) M) varied in the subcellular fractions; it was higher in the guinea-pig (range 31--87%) than in the rat (nonsignificant effect to 40%). A greater percentage of total Na+K+- activated ATPase activity was inhibited in the vas deferens of the guinea pig (56%) than the rat (30%). Differences in the effects of lowered extracellular potassium concentration or ouabain on resting membrane potential (preceding paper) are apparently unrelated to the amount of transport enzyme in the vasa deferentia or the two species, or to its relative sensitivity to ouabain.
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PMID:Species differences in sodium-potassium adenosine triphosphatase activity in the smooth muscle of the guinea-pig and rat vas deferens. 21 53

Ultrastructural distribution of acid phosphatase and adenosine triphosphatase was studied in the receptor elements of HERBST and GRANDRY sensory corpuscles. Acid phosphatase activity was established in the elements of smooth and rough endoplasmic reticulum of perineural capsule cells, as well as in the secondary lysosomes of all cell types. Particular interest was paid on the activity of myelin-like dense bodies and some clear core vesicles belonging to the axoplasm of receptor nerve fibres. Adenosine triphosphatase activity was established on the membranes of receptor structures and pinocytotic vesicles. More deposits of electron dense material were localized on the axolemma of the non-myelinated portions of the receptor nerve fibres. The functional significance and importance of the both enzymes in the receptor structures was discussed.
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PMID:Cytochemical localization of acid phosphatase and adenosine triphosphatase in some avian mechanoreceptors. 21 19

Enzyme histochemical and immunohistochemical techniques were used to examine palatine tonsils and aggregated lymphoid follicles (Peyer's patches) of the ileum in 6- to 9-day-old and in 6-month-old pigs. Histochemical techniques were used to detect alpha-naphthyl-acetate esterase (ANAE), alpha-naphthyl-butyrate esterase (ANBE), beta-glucuronidase, adenosine triphosphatase (ATPase), and acid phosphatase (AcP). Nonspecific esterases (ANAE, ANBE) were detected in macrophages, T-cell area lymphocytes, eosinophils, fibroblastic reticular cells (FRC), follicular dendritic cells (FDC), and interdigitating cells (IDC). beta-Glucuronidase reactivity was strong in macrophages, eosinophils, FDC, and IDC, and weaker in FRC. Adenosine triphosphatase reactivity was detected in B-cell area lymphocytes, FDC, FRC, and IDC. Cell types with acid phosphatase reactivity were macrophages, FDC, FRC, and IDC. Nonepithelial cells of tonsils and aggregated lymphoid follicles of the ileum had similar enzymatic reactions. In Peyer's patches, however, epithelial cells were positive for all enzymes studied; in tonsils, only nonspecific esterases were detected. Immunoperoxidase techniques were used to detect S-100 protein and cytoplasmic immunoglobulins (IgG, IgM, and IgA). The S-100 protein was detected in lymphocytes, FDC, and FRC of tonsils and Peyer's patches; in tonsillar epithelial and endothelial cells; and in IDC of Peyer's patches.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Histochemical and immunohistochemical study of the mucosal lymphoid system in swine. 138 98


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