Adenosine triphosphatases

Contraction of muscle follows an increase of Ca " in the muscle cell as a result of nerve stimulation. This initiates processes which cause the proteins myosin and actin to be drawn together making the cell shorter and thicker. The return of the Ca " to its storage site, the sarcoplasmic reticulum, by an active pump mechanism allows the contracted muscle to relax (27). Calcium ion, also a factor in the release of acetylcholine on stimulation of nerve cells, influences the permeabiUty of cell membranes activates enzymes, such as adenosine triphosphatase (ATPase), Hpase, and some proteolytic enzymes and facihtates intestinal absorption of vitamin B 2 [68-19-9] (28). 

Eisenberg, E. Moos, C. (1970). Actin activation of heavy-meromyosin adenosine triphosphatase. J. Biol. Chem. 245,2451-2456. 

Stein, L.A., Schwarz, R., Chock, P.B., Eisenberg, E. (1979). Mechanism of actomyosin adenosine triphosphatase. Evidence that adenosine 5 -triphosphate hydrolysis can occur without dissociation of the actomyosin complex. Biochemistry 18, 3895-3909. 

Trentham, D.R., Bardsley, R.G., Eccleston, J.F., Weeds, G. (1972). Elementary processes of the magnesium ion-dependent adenosine triphosphatase activity of heavy meromyosin. Biochem. J. 126, 635-644. 

Basha PM, Nayeemunnisa. 1993a. Effect of methyl parathion on Na, K, and Mg adenosine triphosphatase activity in developing central nervous system in rats. Indian J Exp Biol 31 785-787. 

AP = alkaline phosphatase ATPase = adenosine triphosphatase Cardio = cardiovascular d = day(s) Endocr = endocrine F = female Gastro = gastrointestinal Gn pig = guinea pig GOT = glutamic-oxaloacetic transaminase GPT = glutamic-pyruvic transaminase Hemato = hematological hr = hour(s) LDH = lactate dehydrogenase LOAEL = lowest-observable-adverse-effect level M = male Musc/skel = musculoskeletal NOAEL = no-observable-adverse-effect level ... 

Adenosine triphosphatase 4 Highly reactive compounds multitarget... 

Harris, W.E. and Stahl, W.L. (1980). Oiganisation of thiol groups of electric eel electric organ Na/K ion stimulated adenosine triphosphatase, studied with bifunctional reagents. Biochem. J. 185, 787-790. 

ATHERO-ELAM A montxyte adhesion molecule ATL Adult T cell leukaemia ATP Adenosine triphosphate ATPase Adenosine triphosphatase ATP-ys Adenosine 3 thiotriphosphate AITP Autoimmune thrombcKytopenic purpura AUC Area under curve AVP Arginine vasopressin... 

T. K. Hodges, R, T. Leonard, C. E, Bracker, and T. W. Keenan, Purification of an ion-stimulated adenosine triphosphatase from plant roots association with plasma membranes. Proc. Nat. Acad. Sci. U.S.A. 69 3307 (1972). 

The ventricular action potential is depicted in Fig. 6-2.2 Myocyte resting membrane potential is usually -70 to -90 mV, due to the action of the sodium-potassium adenosine triphosphatase (ATPase) pump, which maintains relatively high extracellular sodium concentrations and relatively low extracellular potassium concentrations. During each action potential cycle, the potential of the membrane increases to a threshold potential, usually -60 to -80 mV. When the membrane potential reaches this threshold, the fast sodium channels open, allowing sodium ions to rapidly enter the cell. This rapid influx of positive ions... 

Bragg, P.D., and Hou, C. (1975) Subunit composition, function, and spatial arrangement in the Ca2+-and Mg2+-activated adenosine triphosphatases of Escherichia coli and Salmonella typhimurium. Arch. Biochem. Biophys. 167, 311-321. 

Hiratsuka, T. (1987) Nucleotide-induced change in the interaction between the 20- and 26-kilodalton heavy-chain segments of myosin adenosine triphosphatase revealed by chemical cross-linking via the reactive thiol SH2. Biochemistry 26, 3168. 

Hiratsuka, T. (1988) Cross-linking of three heavy-chain domains of myosin adenosine triphosphatase with a trifunctional alkylating agent. Biochemistry 27, 4110. 

Of the following diuretic agents, which would be least likely to indirectly cause an increased binding of digoxin to cardiac tissue sodium-potassium-adenosine triphosphatase (Na K ATPase) ... 

PPIs block gastric acid secretion by inhibiting hydrogen potassium adenosine triphosphatase in gastric parietal cells, which results in profound and long-lasting antisecretory effects. 

Mitochondria (45-56) are organelles possessing a double membrane, the inner of which is invaginated as cristae. An intermembrane space exists between the inner and outer membranes. The inner membrane consists of an unusually high amount of protein and possesses spherically shaped particles approx 9 nm in diameter. These particles appear to be equivalent to F0, Fb and adenosine triphosphatase. In contrast to the inner membrane, the outer membrane is smooth and appears to be connected to the smooth er. This membrane is permeable to all molecules of 10,000 Dalton or less. A mitochondrial matrix is enclosed by the inner membrane and consists of a ground substance of particles, nucleoids, ribosomes, and electron-transparent regions containing DNA. 

Curtis LR, Mehendale HM. 1981. Hepatobiliary dysfunction and inhibition of adenosine triphosphatase activity of bile canaliculi-enriched fractions following in vivo mirex, photomirex, and chlordecone exposures. Toxicol Appl Pharmacol 61 429-440. 

An in-depth study of DNA repair systems (Aravind et al., 1999a) has concluded that few, if any, repair proteins occur with identical collinear domain arrangements in all three kingdoms of life. Approximately 10 enzyme families of adenosine triphosphatases (ATPases), photolyases, helicases, and nucleases were identified that are all likely to have been present in the cenancestor. These enzymatic domains are accompanied in DNA repair proteins by numerous regulatory domains. This indicates that the domain architectures of these proteins are labile, with incremental addition and/or subtraction of domains to conserved cores to be a common phenomenon except in the most closely related species. 

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