The preparation of 32P-labelled adenosine polyphosphates

Abstract

The reaction of orthophosphate with adenosine 5[image]-monophosphate, diphosphate and triphosphate in the presence of NN[image]-dicyclohexylcar-bodiimide was used for the NN[image] preparation of labeled adenosine polyphosphates. The adenosine diphosphate so prepared is labeled exclusively in the terminal phosphate group. The adenosine triphosphate and adenosine tetraphosphate so prepared are labeled in the terminal phosphate group, and to a lesser extent in the penultimate phosphate group. A feature of the method is that carrier-free labeled orthophosphate can be used without prior dilution with unlabeled orthophosphate. The reaction of pyrophosphate with adenosine 5[image]-monophosphate in the presence of NN[image]-dicyclohexylcarbodiimide was used for the preparation of labeled ATP. The ATP so prepared is labeled in the beta- and gamma-phosphate groups to an equal extent. An improved method for the preparation of NN[image]-dicyclohexylcarbodiimide is described.