title: Arginine modification with butanedione inhibits the potassium ATPase of Streptococcus faecalis.
abstract: The K+-ATPase of Streptococcus faecalis is inhibited by incubation with the arginine-modifying reagent 2,3-butanedione. The inactivation proceeds by pseudo - first order kinetics and a double-logarithmic plot of the pseudo - first order rate constants versus reagent concentrations yields a reaction order of 1.14 with respect to butanedione. Partially inactivated ATPase exhibits a decreased maximal velocity but the same affinity for ATP, as compared to the native enzyme. Butanedione modification is inhibited by adenine nucleotides. These results indicate the involvement of most likely one crucial arginyl residue in adenine nucleotide binding by the ATPase.
mesh_terms: D000251:Adenosine Triphosphatases / Q000037:antagonists & inhibitors*; D001120:Arginine; D001665:Binding Sites / Q000187:drug effects; D027682:Cation Transport Proteins; D013293:Enterococcus faecalis / Q000201:enzymology*; D004852:Epoxy Compounds / Q000494:pharmacology*; D004988:Ethers, Cyclic / Q000494:pharmacology*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics
chemical_list: D027682:Cation Transport Proteins; D004852:Epoxy Compounds; D004988:Ethers, Cyclic; C007366:diepoxybutane; D001120:Arginine; D000251:Adenosine Triphosphatases; C022761:potassium transporting ATPase