Formation and characterization of crosslinks, including Tyr–Trp species, on one electron oxidation of free Tyr and Trp residues by carbonate radical anion
Juan David Figueroa, Ana María Zárate, Eduardo Fuentes-Lemus, Michael J. Davies, Camilo López‐Alarcón
Abstract
'-dityrosine and isodityrosine from Tyr, and three ditryptophan dimers from Trp. When mixtures of Tyr and Trp were illuminated in an identical manner, Tyr-Trp crosslinks were detected together with dityrosine and ditryptophan dimers. These results indicate that there is a balance between the formation of these three classes of crosslinks, which is dependent on the Tyr and Trp concentrations. The methods reported here allow the generation of significant yields of isolated Tyr-Trp adducts and their characterization. This technology should facilitate the detection, and examination of the biological consequences of Tyr-Trp crosslink formation in complex systems in future investigations.