Deoxyribonucleic acid strand break induced by the hydroxy radical-generating cyclic peroxide, 4-ethoxy-1,4-dihydro-2,3-benzodioxin-1-ol.

Abstract

Deoxyribonucleic acid (DNA) strand break caused by a synthetic cyclic peroxide, 4-ethoxy-1,4-dihydro-2,3-benzodioxin-1-ol (Bd) was studied by both ethidium bromide fluorescence quenching and agarose gel electrophoresis. The Bd-mediated DNA strand break occurred dependently on temperature and also on Bd concentration. The reaction proceeded at a temperature higher than 30 degrees C (decomposition temperature of Bd), indicating that the reactive species generated by Bd-decomposition are responsible for the reaction. The reaction was protected by 1,4-diazabicyclo[2.2.2]octane and NaN3, and also moderately by OH radical scavengers such as Na-benzoate and NaBr. Possible involvement of active oxygen radicals including OH radical in the DNA strand break is discussed in relation to the mechanism of Bd decomposition.