title: Se-(8-azidoadenosyl)[75Se]selenomethionine as a photoaffinity label for S-adenosylmethionine binding proteins.
abstract: A method is described for the synthesis and purification of the photoaffinity label Se-(8-azidoadenosyl)[75Se]selenomethionine. This photoaffinity label can be used to specifically and covalently label the S-adenosylmethionine binding site of proteins that use this cofactor, as exemplified by labeling of thioether methyltransferase. By utilizing the gamma-emitting isotope of selenium, Se-(8-azidoadenosyl)[75Se]selenomethionine eliminates the need for the impregnation of acrylamide gels with fluorographic enhancers and dilution of liquid samples into scintillation cocktails, as is required with the commonly used methyl-3H-labeled and 35S-labeled S-(8-azidoadenosyl)methionine.
authors.affiliation: University of Louisville, Department of Biochemistry, Kentucky 40292.
authors.forename: D R
authors.initials: DR
authors.lastname: Warner
authors.forename: J L
authors.initials: JL
authors.lastname: Hoffman
mesh_terms: D000345:Affinity Labels; D001665:Binding Sites; D002352:Carrier Proteins; D002851:Chromatography, High Pressure Liquid; D008780:Methyltransferases / Q000302:isolation & purification; D012436:S-Adenosylmethionine / Q000378:metabolism*; D012644:Selenium Radioisotopes; D012645:Selenomethionine / Q000031:analogs & derivatives* / Q000138:chemical synthesis; D014316:Tritium
chemical_list: D000345:Affinity Labels; D002352:Carrier Proteins; D012644:Selenium Radioisotopes; D014316:Tritium; C071818:Se-(8-azidoadenosyl)selenomethionine; D012436:S-Adenosylmethionine; D012645:Selenomethionine; D008780:Methyltransferases; C055340:S-adenosyl methionine thioether S-methyltransferase