title: Adenosine triphosphatase in isolated membranes of Staphylococcus aureus.
abstract: The preparation of cytoplasmic membranes from suspensions of Staphylococcus aureus lysed by an enzyme recently isolated in these laboratories is described. These membranes contained: protein, 34.4%; ribonucleic acid, 6.6%; lipids, 34.5%; and total phosphorus, 1.4%. Such membranes exhibited adenosine 5'-triphosphatase (E.C. 3.6.1.3) activity, liberating orthophosphate at an initial rate of 0.53 mumole per min per mg of protein under optimal conditions. The enzyme was Mg(++)-dependent and K(+)- or Na(+)-stimulated. Maximal activity was observed with a molar adenosine 5'-triphosphate (ATP) to Mg(++) ratio of 1. One mole of orthophosphate was liberated per mole of ATP; the other product of digestion was adenosine 5'-diphosphate. Inorganic pyrophosphate and the 5'-triphosphates of guanosine, uridine, and cytidine were also attacked by membrane preparations, but more slowly than ATP. Ouabain, p-chloromercuribenzoate, and 2,4-dinitrophenol did not alter adenosine triphosphatase activity, whereas both Atebrine and chlorpromazine were inhibitory.
mesh_terms: D000251:Adenosine Triphosphatases / Q000032:analysis* / Q000037:antagonists & inhibitors; D001426:Bacterial Proteins / Q000032:analysis; D002118:Calcium / Q000494:pharmacology; D002462:Cell Membrane / Q000032:analysis / Q000201:enzymology*; D002854:Chromatography, Paper; D006863:Hydrogen-Ion Concentration; D008274:Magnesium / Q000494:pharmacology; D008566:Membranes; D009711:Nucleotides / Q000378:metabolism; D012329:RNA, Bacterial / Q000032:analysis; D013210:Staphylococcus / Q000032:analysis / Q000201:enzymology*
chemical_list: D001426:Bacterial Proteins; D009711:Nucleotides; D012329:RNA, Bacterial; D000251:Adenosine Triphosphatases; D008274:Magnesium; D002118:Calcium