title: Inhibition of mitochondrial ATPase by Hg++ ions.
abstract: 1. Maximum heart mitochondrial ATPase activity is displayed in the presence of an ATP/Mg++ ratio of 0.6--1.2. Under these conditions, mercury ions inhibit ATPase activity of both the mitochondria and the isolated enzyme. In both cases, inhibition occurs within concentration limits of 1--1.5X10(-4) M. 2. The inhibitory effect of free Hg++ ions can be abolished by converting them to a complex with ethylenediaminetetraacetic acid [EDTA]. 3. The inhibitory effect of Hg++ ions on mitochondrial ATPase can be attributed to their nonspecific action on functional groups of the active centre or to breakdown of the quaternary structure of the protein molecule of the enzyme.
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism*; D000818:Animals; D002417:Cattle; D004492:Edetic Acid / Q000494:pharmacology; D066298:In Vitro Techniques; D008628:Mercury / Q000494:pharmacology*; D008929:Mitochondria, Heart / Q000201:enzymology*
chemical_list: D004492:Edetic Acid; D000251:Adenosine Triphosphatases; D008628:Mercury