The enzymic degradation of adenosinetriphosphate

Abstract

The enzymic assay of adenosinetriphosphate and adenosinediphosphate, either singly or in mixtures, was explored by use of myosin adenosinetriphosphatase acting alone and in conjunction with myokinase. A disadvantage of the method was the slow hydrolysis of adenosintriphosphate in the final stages of the reaction. Metallic salts of adenosinetriphosphate were shown to be unstable and to break down on storage to adenylic acid and inorganic pyrophosphate, and to a lesser extent to adenosinediphosphate and inorganic phosphate. The best prepns. of adenosinetriphosphate were at least 95% pure. The possibility that some impurity was present was not excluded. The use of potato apyrase for the assay of adenosinetriphosphate was restricted by its contamination with a nucleotidase and an inorganic pyrophosphatase. Both in fresh and in rigor muscle, the adenosinediphosphate present was less than 5% and probably greater than 1% of the labile nucleotide P.