Open AccessSpecific photoaffinity labeling induced by energy transfer: application to irreversible inhibition of acetylcholinesterase.
Author(s) -
Maurice Goeldner,
Christian Hirth
Publication year - 1980
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.77.11.6439
Subject(s) - photoaffinity labeling , chemistry , reagent , electrophile , affinity label , tryptophan , acetylcholinesterase , enzyme , affinity labeling , stereochemistry , photochemistry , biochemistry , binding site , organic chemistry , amino acid , catalysis
p-Dimethylaminobenzene diazonium fluoroborate belongs to a class of potential photoaffinity labeling reagents which, by irradiation, produces a highly reactive electrophilic species. In addition, it can be photodecomposed by photoexcited tryptophan derivatives (e.g., N-acetyltryptophanamide and tryptophan residues belonging to acetylcholinesterase) by an energy transfer reaction. This substance is a competitive inhibitor of acetylcholinesterase (acetylcholine acetylhydrolase, EC 3.1.1.7) and is able to inactivate the enzyme either by photoaffinity labeling after irradiation at 410 nm or by an energy transfer reaction after irradiation at 295 nm. The efficiency of this method is demonstrated by an increase of the rate of enzyme inactivation as well as by a decrease of nonselective labeling with a radioactive inhibitor p-[methyl-3H]-dimethylaminobenzene diazonium fluoroborate.