title: Photoaffinity labeling: theory and practice.
abstract: The potential for generating a reactive reagent in situ by photoexcitation and for labeling sites not containing reactive nucleophilic residues provides photoaffinity labeling with a special advantage in the study of ligand-binding sites. There are, however, problems in the application of the photoaffinity technique. A number of concerns about this approach are examined by using as a background studies with arylazido-beta-alanyl nucleotide probes developed in this laboratory. It is concluded that photoaffinity labeling is likely to emerge as one of the major techniques for elucidating structure-function relationships within biological membranes. In the future the design of photoprobes with shorter activation half-lives may make it possible to investigate time-dependent (i.e., conformational) changes occurring at the active site of enzymes and within complex ligand-binding sites.
mesh_terms: D000255:Adenosine Triphosphate / Q000031:analogs & derivatives; D000345:Affinity Labels; D001386:Azides; D010777:Photochemistry; D013329:Structure-Activity Relationship
chemical_list: C012761:3'-O-(3-(N-(4-azido-2-nitrophenyl)amino)propionyl)adenosine-5'-triphosphate; D000345:Affinity Labels; D001386:Azides; D000255:Adenosine Triphosphate