Formation and Decomposition of a Phosphorylated Intermediate in the Reaction of Na+-K+ Dependent ATPase*

Abstract

A simple mixing apparatus driven by solenoids was devised to follow a rapid reaction. The partial reactions of Na⁺-K⁺ dependent ATPase (ATP phosphohydrolase, EC 3.6.1.3) were separately investigated in the presence of 1mM MgCl₂ and monovalent salts at pH8.5 and 15°C, and the following results were obtained.