[Identification and catalytic properties of Mg2+-dependent ATP-hydrolase of cytoplasmic membrane of Bacillus sp. B4253 capable of gold accumulation].

Ca2+-independent, Mg2+-dependent ATP-hydrolase fermentative activity consisting of two components--azide-sensitive and azide-resistant ones has been identified in cytoplasmic membrane of Bacillus sp. B4253 capable to gold accumulation in ionic and colloid forms. The authors have characterized properties of the azide-resistant component of ATP-hydrolase reaction: dynamics of accumulation of one of the reaction products--inorganic phosphate P(i); dependence of ATP hydrolysis rate on the membrane protein content; pH-dependence; sensitivity of ATP-hydrolase activity to the change of reagents (ATP, Mg2+) concentration, as well as to the effect of some specific and nonspecific inhibitors of ion-transporting Mg2+-dependent ATP-hydrolase systems (ouabain, tapsigargin, eocine Y, La ions). It is supposed that the obtained experimental data can be used for the following study of molecular and membrane mechanisms of gold accumulation in Bacillus sp. B4253.