Abstract Photochemical mapping of nucleophiles in close proximity to the active site Cys149 of rabbit glyceraldehyde-3-phosphate dehydrogenase (GAPDH) was demonstrated based on the nucleophilic aromatic photosubstitution reaction using two regioisomers of alkoxy- fluoro-nitro-substituted benzenes. Two photophores were covalently attached to the active site SH group of GAPDH and the protein was subjected to photolysis then to the cyanogen ...
