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Time-resolved study of thymine dimer formation.

Sylvie Marguet·Dimitra Markovitsi
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Abstract

The formation of thymine dimers in the single-stranded oligonucleotide, (dT)20, is studied at room temperature by laser flash photolysis using 266 nm excitation. It is shown that the (6-4) adduct is formed within 4 ms via a reactive intermediate. The formation of cyclobutane dimers is faster than 200 ns. The overall quantum yield for the (6-4) formation is (3.7 +/- 0.3) x 10-3, and that of the cyclobutane dimers is (2.8 +/- 0.2) x 10-2. No triplet absorption is detected, showing that either the intersystem crossing yield decreases by 1 order of magnitude upon oligomerization (<1.4 x 10-3) or the triplet state reacts with unit efficiency in less than 200 ns to yield cyclobutane dimers.

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PhotolysisPoly TPyrimidine DimersThymidine MonophosphateJournal ArticleResearch Support, Non-U.S. Gov't

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Sylvie Marguet, Dimitra Markovitsi. 2005-04-27. Time-resolved study of thymine dimer formation.. https://doi.org/10.1021/ja050648h

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