title: A simple assay method for determination of the specific radioactivity of the gamma-phosphate group of 32P-labelled ATP.
abstract: A simple and rapid assay method is described for determining the specific radioactivity of the gamma-phosphate group of 32P-labelled ATP. Labelled ATP is incubated with cyclic AMP, cyclic AMP-dependent protein kinase and histone H2A under conditions leading to maximum phosphorylation of the histone. The specific radioactivity of the gamma-phosphate group of the 32P-labelled ATP is calculated from the total amount of [32P]Pi incorporated into a standard amount of histone. This assay method uses inexpensive commercially available materials, and it yields an accurate specific radioactivity with as little as 0.25 nmol of 32P-labelled ATP.
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism*; D000242:Cyclic AMP / Q000378:metabolism; D006657:Histones / Q000378:metabolism; D008099:Liver / Q000166:cytology / Q000378:metabolism; D008722:Methods; D010761:Phosphorus Radioisotopes; D011494:Protein Kinases / Q000378:metabolism
chemical_list: D006657:Histones; D010761:Phosphorus Radioisotopes; D000255:Adenosine Triphosphate; D000242:Cyclic AMP; D011494:Protein Kinases