A MODIFICATION TO AN ENZYMATIC METHOD FOR THE PREPARATION OF (ALPHA-P-32) ATP WITH A HIGH SPECIFIC ACTIVITY

A modification of the procedure reported by JOHNSON and WALSETH(1) for the preparation of (alpha-P-32)ATP : (gamma-P-32)GTP with a specific activity of more than 5000 Ci/mmol was made firstly, then it was used as the phosphate donor in the reaction catalyzed by the polynucleotide kinase, to transfer its radioactive phosphate to the 5'-position of t he 3'-AMP, resulting (5'-P-32)3'-ADP. After that, (5'-P-32)3'-ADP was hydrolysed to (5'-P-32)AMP under the catalysis of Nuclease P1, the lat e was then phosphorylated to produce (alpha-P-32)ATP by the action of myokinase and pyruvate kinase. By this method, we firstly prepared (al pha-P-32)ATP with a specific activity of more than 4000 Ci/mmol which was measured by HPLC analysis.