Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.6.3.14 (ATP synthase)
 7,042 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Heparin (1-10 micrograms/ml) inhibits the Ca2+ transport ATPases found in the sarcoplasmic reticulum of skeletal muscle, the plasma membrane of red cells, and the dense tubular system of blood platelets, but not the (Na+ + K+)-ATPase or the mitochondrial F1-ATPase. In the reversal of the Ca2+ pump, heparin uncouples the synthesis of ATP from Ca2+ efflux and inhibits the phosphorylation of the sarcoplasmic reticulum Ca(2+)-ATPase by Pi, but has no effect the phosphorylation by ATP. The effect of heparin on the muscle Ca(2+)-ATPase is abolished by KCl and NaCl (100 mM) and to a lesser extent by LiCl. These monovalent cations are not effective as antagonists of heparin on the platelet Ca(2+)-ATPase. The effects of heparin are antagonized by the polyamines spermine, spermidine, and ruthenium red. Unlike KCl, polyamines are equally effective in counteracting the effects of heparin in both muscle and platelet Ca(2+)-ATPases. In addition to heparin, the Ca(2+)-ATPases of muscle and blood platelets are also inhibited by dextran sulfate and fucose-branched chondroitin sulfate. The inhibition promoted by these glycosaminoglycans is antagonized by monovalent cations and polyamines in the same manner as heparin. Heparan sulfate, chondroitin sulfate, and hyaluronic acid have not effect on the Ca(2+)-ATPases studied.
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PMID:Uncoupling of muscle and blood platelets Ca2+ transport ATPases by heparin. Regulation by K+. 751 71

Saccharomyces cerevisiae mitochondria have a polyphosphatase activity which is insensitive to a number of inhibitors of mitochondrial ATPase and pyrophosphatase (PPase). Heparin (20 micrograms/ml) and EDTA (0.5 mM) do not inhibit ATPase and PPase activities but completely suppressed mitochondrial polyphosphatase activity. The mitochondrial polyphosphatase activity is maximal at neutral pH; it is inhibited by monovalent cations in the presence of Tris+ (K+ > Na+ > NH4+), and stimulated by bivalent metal cations (Co2+ > Mg2+ > Zn2+ > Mn2+). The polyphosphatase activity does not significantly depend on polyphosphate chain length from 9 to 208 but is more than one order of magnitude higher than activity with tripolyphosphate. Some properties of mitochondrial polyphosphatase activity differ from the characteristics of polyphosphatases of cell envelope, cytosol, vacuoles and nuclei of the same S. cerevisiae strain.
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PMID:[Characteristics of polyphosphatase activity of isolated mitochondria from Saccharomyces cerevisiae]. 899 89