A chromism-based assay (CHROBA) technique for in situ detection of protein kinase activity

A unique chromism-based assay (CHROBA) technique using photochromic spiropyran-containing peptides has been firstly established for detection of protein kinase A-catalyzed phosphorylation. The promising method has advantages that avoid isolation and/or immobilization of substrates to remove excess nonreactive isotope-labeled ATP or fluorescently-labeled anti-phosphoamino acid antibodies from the reaction mixture.