Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.6.1.3 (ATPase)
65,361 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Transitional states of Candida utilis BKM Y-1668 were found during its growth in conditions of chemostat at D of 0.1 hr(-1) and glycerol limit after a shock caused by an extreme pH value (2.2). The optical density of the cells, the amount of dry biomass and protein, the activity of respiration, the content of ATP, and the activity of ATPase decreased, the character of the decrease being that of damped oscillations. Qualitative changes were detected in the activity of respiration, oxygen uptake was not inhibited by cyanide. More glycerol and phosphorus are utilized in processes of vital activity. Therefore, a sharp change of pH values causes profound changes in the metabolism of the yeast cell.
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PMID:[Transitional state of Candida utilis chemostat culture after shock caused by a low pH value of the medium during 1 generation]. 1 73

1. Intracellular electrolytes, and erythrocyte membrane adenosine triphosphatase (ATPase) activity, was studied in twenty patients after renal transplantation. 2. The mean ouabain-sensitive ATPase activity in the erythrocyte membranes of the transplant patients was 122 nmol of inorganic phosphorus (Pi) h-1 mg of tissue-1 (SEM 14), compared with 62 nmol of Pi h-1 mg of tissue-1 (SEM 8) in a group of paired, healthy controls. 3. The increase in ouabain-sensitive ATPase was most marked in the 4 months after transplantation. However, a significant increase in ouabain-sensitive ATPase persisted for more than 8 months after transplantation. 4. This increase in ouabain-sensitive ATPase was associated with a decrease in intracellular sodium in the erythrocytes of the transplant patients.
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PMID:Changes in erythrocyte membrane ouabain-sensitive adenosine triphosphatase after renal transplantation. 12 85

The requirement of actual splitting of ATP for endocytosis in erythrocyte ghosts has been confirmed by use of the ATP analog, 5'-adenylylimidodiphosphate, (AMP-P(NH)P). This compound, in which the oxygen connecting the beta and gamma phosphorus atoms was replaced by an NH group, did not cause endocytosis nor was it a substrate for ATPase activity. AMP-P(NH)P was a competitive inhibitor both for the endocytosis and the Mg2+-ATPase activities. The K1 of AMP-P(NH)P for Mg2+ ATPase activity was 2.0 - 10-4 M and, while the Km of ATP for this activity was also 2.0 - 10-4 M indicating nearly identical affinities of ATP and AMP-P(NH)P for the active site. ADP, or ADP plus orthophosphate, did not cause endocytosis, showing that endocytosis was not due to binding of the products of ATP hydrolysis. Sodium or potassium ion or ouabain had no effect on endocytosis, which eliminated the possibility of involvement of the Na+, K+ ATPase in the endocytosis process. Calcium could not be substituted for magnesium; rather it inhibited endocytosis at the concentration of 1 - 10-3 M. EGTA relieved the inhibitory effect of Ca, which indicated that the binding of calcium to the membrane was reversible. These experimental results reaffirm the conclusion that ATP must be split to engender endocytosis under these conditions. Some characteristic parameters of the hemoglobin-free porcine erythrocyte ghosts were studied in order to characterize the system more adequately.
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PMID:Energy-dependent endocytosis in erythrocyte ghosts. IV. Effects of Ca2+, Na+ +K+, and 5'-adenylylimidodiphosphate. 12 70

The chemical properties of two highly purified preparations of (sodium + potassium)-activated adenosine triphosphatase (NaK ATPase) and their subunits have been compared. One preparation is derived from the rectal gland of the spiny dogfish shark, Squalus acanthias and the other preparation is derived from the electric organ of the electric eel, Electrophorus electricus. Ouabain binding and phosphorylation from [gamma-32-P]ATP for both enzymes ranged from 4000 to 4300 pmol per mg of protein. This gives a stoichiometry for ouabain binding and phosphorylation of 1:1 for both enzymes. The molar ratios of catalytic subunit to glycoprotein was 2:1 for both enzymes, suggesting a minimum molecular weight of 250, 000, which agrees with the molecular weight obtained by radiation inactivation. Assuming that only one of the two catalytic subunits is phosphorylated and binds ouabain per (sodium + potassium)-activated adenosine triphosphatase molecule the data on phosphorylation and ouabain binding also give a molecular weight of 250, 000. The data on phosphorylatiion, ouabain binding, subunit composition, and molecular weight based on radiaion inactivation are thus all internally consistent. A technique has been developed for isolation of pure catalytic subunit and glycoprotein in good yields by preparative sodium dodecyl sulfate-polyacrylamide gel electrophoresis. A variety of chemical studies have been carried out with the purified subunits. The amino acid composition of the catalytic subunit was different from that of the glycoprotein, but the amino acid composition of each of the two subunits was essentially the same for both species. However, the NH2-terminal amino acid for the catalytic subunit was alanine for the rectal gland enzyme and serine for the electric organ enzyme, suggesting some differencesin amino acid sequences for the two species. The NH2-terminal amino acid for the glycoprotein was alanine for the two species. The glycoproteins from both species contained the same carbohydrates but in quite differing amounts. The carbohydrates were glucosamine, sialic acid, fucose, galactose, mannose, and glucose. The release of all the sialic acid from the electric organ enzyme and the release of 40% of the sialic acid from the rectal gland enzyme did not affect (sodium + potassium)-activated adenosine triphosphatase activity. Both enzymes contained the following phospholipids, which accounted for 98 to 100% of the total phospholipid phosphorus: sphingomyelin, lecithin, phosphatidylserine, phosphatidylethanolamine, and phosphatidylinositol. With the exception of phosphatidylethanolamine, and phosphatidylinositol. With the exception of phosphatidylserine, the amount of any phospholipid per mg of enzyme as well as the total phospholipid content were quite different for the two enzymes.
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PMID:Molecular properties of purified (sodium + potassium)-activated adenosine triphosphatases and their subunits from the rectal gland of Squalus acanthias and the electric organ of Electrophorus electricus. 12 22

The distribution of sodium-potassium adenosine triposphatase (Na-K-ATPase) activity in kidney sections has been studied by a method based on the hydrolysis of p-nitrophenyl phosphate in alkaline medium containing dimethyl sulfoxide. The products at each stage in the reaction sequence have been subjected to electron probe microanalysis. The initial product was identified as a mixture of KMgPO4 and Mg(PO4)2, and sequential analysis demonstrated the linearity of conversion of this product to a visible form. In human, rabbit and rat kidneys the distribution of activity was found to be essentially identical, with highest levels located in thick ascending limbs and distal convoluted tubules. The initial reaction was completely potassium dependent and was inhibited by ouabain in concentrations reflecting the relative sensitivity of microsomal Na-K-ATPase in each species. Measurement of initial product phosphorus by means of the electron probe is presented as a practical technique for direct quantitation of Na-K-ATPase activity in identified tubule segments.
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PMID:Renal sodium-potassium adenosine triphosphatase. Optical localization and x-ray microanalysis. 12 10

In dynamics of experimental rickets proteins of rat sceletal muscles were studied after and before physical exercises. Occurrence of rickets was estimated by following concentration of inorganic phosphorus and calcium in blood and by X-ray examination of knee joint. An increase in total amount of sarcoplasmic proteins was observed within the first week of development of the disease. After physical exercices the effect was noticed also within the second week of the development of rickets. Content of fractions of the sarcoplasmic proteins was similar in all animals and within all the periods studied. Within four weeks content of myofibrillar proteins was decreased in rickety rats, which were not subjected to physical exercices. In rats of the both experimental groups the ATPase activity of actomyosin was not distinctly altered within all the periods studied.
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PMID:[Study of proteins of rat skeletal muscles in experimental rickets]. 12 94

Membranes were isolated and purified from nutrient broth-yeast extract- and hexadecane-grown cells of Acinetobacter sp. strain HO1-N. Two membrane fractions were isolated from nutrient broth-yeast extract-grown cells, the cytoplasmic membrane and the outer membrane. In addition to these two membrane fractions, a unique membrane fraction was isolated from hexadecane-grown cells (band 1) and characterized as a lipid-rich, low-density membrane containing high concentrations of hexadecane. The outer membrane preparations of Acinetobacter, obtained from nutrient broth-yeast extract- and hexadecane-grown cells, exhibited a low ratio of lipid phosphorus to protein and contained phospholipase activity and 2-keto-3-deoxyoctulosonic acid. Phosphatidic acid cytidyltransferase, adenosine triphosphatase, and reduced nicotinamide adenine dinucleotide oxidase were recovered almost exclusively in the cytoplasmic membrane fractions. The cytoplasmic membrane fractions contained 20 to 25 polypeptide species on sodium dodecyl sulfate-polyacrylamide gels, and the outer membrane fractions contained 15 to 20 polypeptide species. A major polypeptide species with an apparent molecular weight of approximately 42,000 to 44,000 was found for all outer membrane fractions. The buoyant densities of the cytoplasmic membrane fractions and the outer membrane fractions were closely similar, necessitating their separation by differential centrifugation. Band 1 of hexadecane-grown cells had a ratio of lipid phosphorus to protein that was almost twice that of cytoplasmic membrane and a correspondingly low buoyant density (1.086 g/cm3). Enzyme activities associated with band 1 were identical to those associated with the cytoplasmic membrane. The electrophoretic banding pattern of band 1 was essentially identical to the banding pattern of the cytoplasmic membrane. The phospholipid and neutral lipid compositions of the isolated membrane fractions were determined as qualitatively similar, with significant quantitative differences. The ultrastructure characteristics of the respective membrane fractions were examined by the negative-stain technique.
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PMID:Isolation and characterization of membranes from a hydrocarbon-oxidizing Acinetobacter sp. 13 29

A method is described for isolation of purified myosin from human sceletal muscles. One isoenzyme of myosin, salting out at 35-45% saturation of ammonium sulfate, was found in aqueous extracts of human muscles. Preparations of myosin, obtained by the method described, possessed the following properties: the ratio of extinctions at 280 and 260 nm 1.5-1.6; the Ca2+-activated ATPase activity--0.15-0.26 mM of phosphorus/mg of protein/min. Molecule of human myosin consisted of two heavy and two light chains (by polyacrylamide gel electrophoresis).
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PMID:[Isolation and properties of myosin from human skeletal muscles]. 14 66

Erythrocytes and their isolated membranes display ATP-dependent endocytosis. To localize the enzymes responsible for this phenomenon, the erythrocyte membranes (ghosts) were fractionated under conditions which retained ATPase activity. Fractionation of the ghosts resulted in three fractions: spectrin-actin, the peripheral proteins soluble in high salt, and the smooth membrane containing integral proteins. On the average, 87% of the protein and 88% of the phosphorus of the original ghosts were recovered in these fractions, and all of the kinds of ATP-splitting activities of the membrane were recovered in the smooth membrane. A tiny ATPase activity, detectable by special methodology in spectrinactin, could have been due to contamination with membranous material. Although the purified spectrin-actin did not have a significant ATPase of its own, it stimulated the Ca2+, Mg2+-ATPase of the smooth membrane significantly, suggesting a cooperative interaction between these two fractions. This segregation of the ATPase activities into the smooth membrane, combined with the energy dependence of endocytosis, showed that the smooth membrane must be involved in the energy production for endocytosis. The possibility that the spectrin-actin filaments cooperate with a myosinlike ATPase in the membrane to generate membrane movements is discussed.
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PMID:Peripheral proteins and smooth membrane from erythrocyte ghosts. Segregation of ATP-utilizing enzymes into smooth membrane. 14 43

Dichloromethylene diphosphonate (Cl2MDP) was given at doses of 4 mg/kg and 10 mg/kg daily for 7 days to adult thyroparathyroidectomized rats fed a low calcium diet. Primary metaphyseal trabeculae in Cl2MDP-treated rats were more numerous and longer than in controls. The light and electron microscopic appearance of osteoblasts, osteocytes and osteoclasts were unaltered by Cl2MDP. Bone alkaline phosphatase was significantly elevated in rats given Cl2MDP but adenosine triphosphatase activity was unchanged. Bone fat-free weight, fat-free minus ash weight, and bone calcium and phosphorus concentration were reduced significantly in rats given 10 mg/kg Cl2MDP compared to controls. Bone magnesium concentration was significantly elevated in rats given 10 mg/kg Cl2MDP. Serum calcium and phosphorus concentration were lower in Cl2MDP-treated rats. These results suggest that Cl2MDP is capable of altering bone remodeling, enzyme activity and mineral content, without significantly altering bone cell morphology, independent of the effects of parathyroid hormone, calcitonin, and dietary calcium.
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PMID:Effect of dichloromethylene diphosphonate on morphology, enzyme activity, and ash content of bones of thyroparathyroidectomized rats. 14 84


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