Radiation-induced Crosslinks between Thymine and Phenylalanine

Summary

OH radicals generated by ionizing radiation in aqueous solutions of thymine (T) and phenylalanine (Phe) induce crosslinking between thymine and phenylalanine. The crosslinked products were isolated and characterized by capillary gas chromatography-mass spectrometry. They are formed via OH radical adducts to thymine and phenylalanine and the reaction between dissimilar radicals is greatly favoured (T-Phe:Phe-Phe:T-T=0·46:0·14:0·05). The reaction mechanism presented may serve as a model for radiation or any free radical-induced crosslinks between DNA and proteins.

• DNA protein crosslinks
• capillary GC-MS
• mass spectra
• trimethylsilylation
• OH adducts