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Updated: Aug 11, 2026

A Simple, Rapid, and Quantitative Assay to Measure Repair of DNA-protein Crosslinks on Plasmids Transfected into Mammalian Cells
Published on: March 5, 2018
DNA-protein cross-linking: model systems for pyrimidine-aromatic amino acid cross-linking
Guangxing Sun1, Christopher J Fecko, Robert B Nicewonger
1Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, USA.
Abstract:
[reaction: see text] We have synthesized simple model systems to explore the possibility of photo-cross-linking between the pyrimidine bases and the side chains of the aromatic amino acids. Thymine/phenylalanine and thymine/tyrosine models gave cross-links, and thymine/tryptophan models gave complex mixtures; the cytosine/phenylalanine model was unreactive. The quantum yields for the model cross-linking reactions were 18-46 times smaller than those for thymine dimer formation. Biphotonic excitation contributes little to the yield of these reactions.
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