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)

1. The synthesis of dibutylchloromethyltin chloride, a new covalent inhibitor of the mitochondrial ATP synthase [oligomycin-sensitive ATPase (adenosine triphosphatase)] complex is described, together with a method for preparing dibutylchloro[(3)H]methyltin chloride. 2. Studies with the yeast mitochondrial oligomycin-sensitive ATPase complex show that dibutylchloromethyltin chloride inhibits both the membrane-bound enzyme and also the purified Triton X-100-dispersed preparation. 3. F(1)-ATPase is not inhibited even at 500nmol of dibutylchloromethyltin chloride/mg of protein, and the general inhibitory properties are similar to those of triethyltin, oligomycin and dicyclohexylcarbodi-imide, known energy-transfer inhibitors of oxidative phosphorylation. 4. Binding studies with yeast submitochondrial particles show that dibutylchloromethyltin chloride antagonizes the binding of triethyl[(113)Sn]tin, indicating that there is an interaction between the two inhibitor-binding sites. 5. Unlike triethyltin, inhibition by dibutylchloromethyltin chloride is due to a covalent interaction which titrates a component of the inner mitochondrial membrane present at a concentration of 8-9nmol/mg of protein. 6. All of the labelled component can be extracted with chloroform/methanol (2:1, v/v), and sodium dodecyl sulphate/polyacrylamide-gel electrophoresis of the chloroform/methanol extract indicates that the labelled component has an apparent mol.wt. of 6000-8000. However, t.l.c. reveals the presence of only one labelled component which is lipophilic and non-protein and is distinct from the free inhibitor, mitochondrial phospholipids and the dicyclohexylcarbodi-imide-binding protein (subunit 9). 7. Inhibition of mitochondrial ATPase and oxidative phosphorylation is correlated with specific interaction with a non-protein lipophilic component of the mitochondrial inner membrane which is proposed to be a co-factor or intermediate of oxidative phosphorylation.
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PMID:Dibutylchloromethyltin chloride, a covalent inhibitor of the adenosine triphosphate synthase complex. 14 60

Hydrophobic agents, e.g. methanol, ethanol, isopropanol, acetone and dioxane were shown to induce irreversible inactivation of Na+, K+-adenosine triphosphatase beginning with their concentrations of 20 to 35%, whereas dimethyl sulphoxide exerted similar effect only at concentration of 50% and higher. Urea also irreversibly inactivated Na+, K+-adenosine triphosphatase, beginning with a concentration of about 20%. It was found that, dimethyl sulphoxide contrary to the other hydrophobic agents studied, protected Na+, K+-adenosine triphosphatase against the inactivating (denaturing) action of urea. The highest stabilizing effect of dimethyl sulphoxide was displayed at concentrations from 20 to 30%.
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PMID:[Stabilization of Na+, K+-adenosine triphosphatase by dimethyl sulfoxide under inactivation by urea]. 14 22

1. The proton-translocating adenosine triphosphatase (ATPase) of bovine heart mitochondria was highly purified by extraction of submitochondrial particles with cholate, fractionation with ammonium sulfate, and sucrose gradient centrifugation in the presence of methanol, deoxycholate, and lysolecithin. 2. The preparation had a very low content of phospholipids, respiratory components, and adenine nucleotide transporter. The ATPase activity (14 o 16 micromoles/min/mg at 30 degrees) was dependent on addition of phospholipids. The purified enzyme was reconstituted with phospholipids, coupling factor 1 (F1), and the oligomycin sensitivity-conferring protein (OSCP) yielding vesicles with highly active 32Pi-ATP exchange (up to 260 nanomoles/min/mg at 30 degrees), and a proton pump driven by ATP. Site III oxidative phosphorylation was reconstituted when purified cytochrome oxidase was included. 3. The 32Pi-ATP exchange of the reconstituted vesicles was sensitive to both rutamycin and dichylohexylcarbodiimide but the ATPase activity was sensitive to rutamycin and not to dicyclohexylcarbodiimide. 4. In sodium dodecyl sulfate-acrylamide gel scans of the complex, the subunits of F1, OSCP, and three other major bands with apparent molecular weights of 32,000, 23,000, and about 11,000 were noted. Three other minor bands with estimated molecular weights of 80,000, 70,000, and 52,000 were also detected. These bands apparently represent residual trace amounts of respiratory components. Quantitative assays of individual respiratory components revealed between 0 and 3% contamination. 5. We conclude that the rutamycin-sensitive ATPase complex functions as a reversible ATP-driven proton pump.
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PMID:Purification and properties of the proton-translocating adenosine triphosphatase complex of bovine heart mitochondria. 17 16

A method is described for preparation of membrane vesicles (diameter 80nm) capable of respiration-linked ATP synthesis. Vesicles prepared from succinate-grown bacteria oxidized NADH, succinate and ascorbate plus NNN'N'-tetramethylphenylenediamine; vesicles prepared from methanol-grown bacteria also oxidized methanol and formaldehyde, but they were otherwise identical. The uncoupling agent carbonyl cyanide chlorophenylhydrazone and the adenosine triphosphatase inhibitor dicyclohexylcarbodi-imide both inhibited ATP synthesis, whereas they had no effect on the rate of respiration. Rotenone inhibited ATP synthesis and respiration with NADH as substrate; antimycin A inhibited with succinate as substrate, and cyanide inhibited with all substrates. P/O ratios were usually 0.7-1.3 with NADH, 0.6-1.0 with succinate and 0.2-0.6 with reduced NNN'N'-tetramethylphenylenediamine or methanol as respiratory substrate. When 2,6-dichlorophenol-indophenol was used as an alternative electron acceptor to O(2) (NADH as donor) the P/2e ratio was 1.65. Although these P/O ratios are minimum values, because they do not take into account unknown amounts of uncoupled O(2) consumption, they are consistent with previous proposals [O'Keeffe & Anthony (1978) Biochem, J.170, 561-567] based on measurements of proton translocation in whole cells. The results also confirm that methanol dehydrogenase and cytochromes c and a/a(3) are arranged so that the first step in methanol oxidation is coupled to synthesis of ATP.
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PMID:The microbial metabolism of C1 compounds. Oxidative phosphorylation in membrane preparations of Pseudomonas AM1. 22 Sep 60

The ATP-energy transducing system in membranes of Escherichia coli is inhibited by dicyclohexylcarbodiimide. The protein component of this complex with which carbodiimides covalently react to inhibit function was previously identified by labeling wild type and dicyclohexylcarbodiimide-resistant mutants with dicyclohexyl[14C]carbodiimide (Fillingame, R. H. (1975) J. Bacteriol. 124, 870-883). This specific carbodiimide-reactive protein has now been purified. The protein was extracted from the membrane with chloroform:methanol and chromatographed on DEAE-cellulose and hydroxypropyl Spehadex G-50 in this sulvent mixture. The resultant 700-fold purification yielded a protein that was homogeneous on dodecyl sulfate-acrylamide gel electrophoresis and virtually free of phospholipid. It remained soluble in neutral chloroform:methanol throughout the purification procedure. The amino acid composition of the purified protein was extraordinary in that only 16% of the amino acids present could be considered polar. Histidine, serine, cysteine, and tryptophan were not found. Abnormally high contents of methionine, glycine, alanine, and leucine were present. One mole of lysine and threonine were found/mole of dicyclohexyl[14C]carbodiimide bound. The minimum molecular weight based on the amino acid composition was 8400. The specific carbodiimide-reactive protein has also been purified without prior modification by dicyclohexylcarbodiimide. The unmodified protein eluted from DEAE-cellulose at a higher salt concentration than the dicyclohexylcarbodiimide-modified form, which suggested that the reaction with the carbodiimide neutralized the negative charge. Only one-third of the total carbodiimide-reactive protein in the membrane was modified by dicyclohexylcarbodiimide under conditions which maximally inhibited adenosine triphosphatase activity. These results rais the possibility that the carbodiimide-reactive protein may be present as an oligomer in the energy-transducing complex. The purification of the unmodified carbodiimide-reactive protein should permit assessment of tis biological function, particularly its role in the protein-translocation process that is catalyzed by this energy-transducing complex.
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PMID:Purification of the carbodiimide-reactive protein component of the ATP energy-transducing system of Escherichia coli. 78 71

The release of lipoteichoic acid and mesosomal vesicles to the supernatant buffer during the formation of spherical, osmotically fragile bodies was studied using Streptococcus faecalis ATCC 9790. Autolytic N-acetylmuramidase action was permitted to take place in exponential-phase cells incubated in a buffer which provides an exceptional degree of osmotic stabilization. Both lipoteichoic acid and mesosomal vesicles were relatively rapidly released to the supernatant buffer. Most of the cellular content of lipoteichoic acid (and mesosomal vesicles) was found in the supernatant buffer at incubation times when the cells still retained over 75% of their cell wall. [14-C]- or [3-H]glycerol was used as a label for both cellular lipoteichoic acids and lipid-glycerol. Glycerol in lipoteichoic acid was quantitated after phenol-water and chloroform-methanol treatments and identified by products of acid hydrolysis and its ability to be precipitated by (i) antibodies specific for the polyglycerol-phosphate backbone, (ii) antibodies to the streptococcal group D antigen, and (iii) concanavalin A. Evidence was obtained that lipoteichoic acid was not associated with isolated mesosomal vesicles. Centrifugation of supernates at 200,000 X g sedimented membranous (mesosomal) vesicles and nearly all of the lipid-glycerol present, whereas essentially all of the lipoteichoic acid remained in the supernatant. The sedimented mesosomal vesicles differed from protoplast membrane in their higher lipid-phosphorus to protein ratio and in the absence of detectable levels of two enzymatic activities found in protoplast membranes, adenosine triphosphatase and polynucleotide phosphorylase. Both types of membranes were found to contain DD-carboxypeptidase and LD-transpeptidase activities at nearly the same specific activities. No evidence was obtained for the association of autolytic N-acetylmuramidase activity with either type of membrane preparation.
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PMID:Cellular localization of lipoteichoic acid in Streptococcus faecalis. 80 56

An endogenous sodium pump inhibitor has been purified from human plasma. The purification scheme involved large scale dialysis, extraction of lyophilized dialysate by methanol followed by preparative and semipreparative scale reverse-phase high-performance chromatography. A single peak of biologically active material was obtained enriched by a factor of greater than 10 billion. This material showed high chromatographic polarity, was inactivated by charring, strong acid, or alkali, and was resistant to short-term boiling. The purified material had a molecular weight between 300 and 900 g/mol and was insensitive to type I esterase and a variety of proteolytic enzymes. The purified factor inhibited the ouabain-sensitive uptake of 86Rb by human erythrocytes, binding of [3H]ouabain, and activity of dog kidney Na,K-adenosine triphosphatase (ATPase) with high affinity (less than 0.3 nM) in a time- and dose-dependent manner. Maximally effective concentrations of the digitalislike factor showed no effect on either human red blood cell Mg- or Ca-ATPase, rabbit muscle sarcoplasmic reticulum Ca-ATPase, or guinea pig stomach H,K-ATPase. The purified material is a highly potent selective inhibitor of the ion transport, receptor, and hydrolytic functions of the sodium pump. The characteristic properties of this substance suggest it may be a mammalian endogenous digitalis and may be similar to the sodium transport inhibitor detected in the plasma of volume-sensitive forms of experimental and human hypertension.
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PMID:Isolation and characterization of a sodium pump inhibitor from human plasma. 254 19

Phosphoinositide content was measured in erythrocyte membranes from 11 patients with cystic fibrosis (CF) and from 12 control subjects to determine whether altered levels of phosphatidylinositol-4-phosphate (Ptdlns4P) or phosphatidylinositol-4,5-bisphosphate (Ptdlns(4,5)P2) are responsible for the decrease in Ca2+-adenosine triphosphatase (Ca2+-ATPase) activity in this disorder. Isolated membranes were extracted with an acidified chloroform-methanol solvent system. The recovered lipids were separated by one-dimensional thin-layer chromatography and quantified with a colorimetric assay for phosphorus. The results are expressed in molar percent, moles of phosphoinositide times 100 divided by the total number of moles of phospholipid per membrane. The means +/- SEM of Ptdlns(4,5)P2, Ptdlns4P, and phosphatidylinositol (Ptdlns) in CF membranes (1.07 +/- 0.18, 1.02 +/- 0.22, and 2.32 +/- 0.36 molar percent, respectively) were indistinguishable from controls (0.91 +/- 0.14, 0.85 +/- 0.12, and 2.21 +/- 0.32 molar percent, respectively) (P greater than 0.20 for all three pairs). The accuracy of quantitative recovery throughout the procedure was determined by adding a radioactive internal standard, L-3-phosphatidyl[2-3H]inositol to 10 membrane preparations. Although quantitative recoveries, as determined by percent radioactivity recovered, varied from 54% to 92%, mean Ptdlns(4,5)P2, Ptdlns4P, and Ptdlns levels appropriately corrected from tracer loss were still indistinguishable between the two groups. We conclude that absolute phosphoinositide levels are not altered in cystic fibrosis erythrocyte membranes and that the differences in Ca2+-ATPase activity cannot be explained on this basis.
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PMID:Phosphoinositide content of erythrocyte membranes in cystic fibrosis. 283 Mar 55

The effects of some aromatic hydrocarbons, aliphatic chlorinated hydrocarbons, and alcohols on adenosine triphosphatase (ATPase) activity in human erythrocyte ghost membrane were studied in vitro. Both aromatic and chlorinated aliphatic hydrocarbons inhibited this activity dose-dependently, the inhibition of total ATPase activity being clearer than that of magnesium-activated ATPase. Of the alcohols studied, methanol had no effect on the ATPase activity, but ethanol, propranolol, and butanol were slightly enzyme-activating at high concentrations. The enzyme-inhibiting potency of organic solvents was generally related to their lipid solubilities, but 1,1,2,2-tetrachloroethane was a potent enzyme inhibitor despite its low lipid solubility. This findings indicates that, eg, the molecular structure of solvents may modulate their enzyme inhibition. In the presence of Triton-X-100, toluene did not cause any changes in the activity of total ATPase, and the combined effect of the two compounds was slight. Triton-X-100 also caused a significant solubilization of membrane proteins although even the highest toluene concentrations did not. These results show that organic solvents may cause their membrane effects by acting directly on membrane-bound integral proteins such as ATPase. This action is not only dependent on the lipid solubility of the compounds, but also on their molecular structure.
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PMID:Effects of industrial organic solvents on human erythrocyte membrane adenosine triphosphatase activities in vitro. 296 75

Radiation inactivation technique was employed to measure the functional size of adenosine triphosphatase of spinach chloroplasts. The functional size for acid-base-induced ATP synthesis was 450 +/- 24 kilodaltons; for phenazine methosulfate-mediated ATP synthesis, 613 +/- 33 kilodaltons; and for methanol-activated ATP hydrolysis, 280 +/- 14 kilodaltons. The difference (170 +/- 57 kilodaltons) between 450 +/- 24 and 280 +/- 14 kilodaltons is explained to be the molecular mass of proton channel (coupling factor 0) across the thylakoid membrane. Our data suggest that the stoichiometry of subunits I, II, and III of coupling factor 0 is 1:2:15. Ca2+- and Mg2+-ATPase activated by methanol, heat, and trypsin digestion have a similar functional size. However, anions such as SO3(2-) and CO3(2-) increased the molecular mass for both ATPase's (except trypsin-activated Mg2+-ATPase) by 12-30%. Soluble coupling factor 1 has a larger target size than that of membrane-bound. This is interpreted as the cold effect during irradiation.
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PMID:Radiation inactivation analysis of chloroplast CF0-CF1 ATPase. 296 17


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