Effects of Various Inorganic Cations on the Catalytic Action of Molybdate on ATP Hydrolysis

　The influence of various cations on the catalytic effect of molybdate on the ATP hydrolysis was studied．

　1．All divalent cations examined, namely calium, magnesium, cobalt, nickel, copper，cadmium and zinc ions, activated remarkably the molybdate action．Sodium and potassium ions did not show significant activation．

　2．The accelerating effect of magnesium and calcium ions on the catalytic activation of molybdate was examined at various pHs．This effect was remarkable at pH around 4 to 5 and could not be observed below 2．