title: Cross-linking of ribosomal proteins by 4-(6-formyl-3-3-azidophenoxy)butyrimidate, a heterobifunctional, cleavable cross-linker.
abstract: For the identification of neighbor relationships between proteins in biological systems 4-(6-formyl-3-azidophenoxy)butyrimidate (FAPB-imidate), a heterobifunctional, cleavable cross-linker was synthesized. The reagent has an imido ester at one end, which is used for the attachment to amino groups of a specific protein whose environment has to be characterized. At the other end, the reagent has both an azido and an aldehyde group. The azido group can be used to cross-link the protein photochemically to a variety of chemical groups of neighboring proteins. The aldehyde group is able to cross-link the protein by reductive alkylatin to amino groups of neighboring proteins. In both cases, the cross-linker can be made radioactive with NaB3H4. the cross-linked complexes can be split at the band originating from the imidate group by treatment with ammonia. Hereby, the radioactive cross-linker remains covalently attached to the unknown neighboring protein, which can be therefore easily identified. In order to explore the usefulness of FAPB-imidate as a cross-linking agent, the compound was attached to ribosomal protein L7. With this modified L7, the existence of the well-known complex between L7 and ribosomal protein L10 could be demonstrated by the photochemical procedure. By the chemical procedure, the presence of dimers of L7 in solution could be shown.
mesh_terms: D001386:Azides; D055598:Chemical Phenomena; D002621:Chemistry; D007094:Imides; D007096:Imidoesters; D007202:Indicators and Reagents; D008970:Molecular Weight; D010084:Oxidation-Reduction; D012269:Ribosomal Proteins; D013056:Spectrophotometry, Ultraviolet
chemical_list: C019394:4-(6-formyl-3-azidophenoxy)butyrimidate; D001386:Azides; D007094:Imides; D007096:Imidoesters; D007202:Indicators and Reagents; D012269:Ribosomal Proteins