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arXiv · 1112.2731

Reactive Molecular Dynamics study on the first steps of DNA-damage by free hydroxyl radicals

Ramin M. Abolfath·A. C. T. van Duin·Thomas Brabec
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Abstract

We employ a large scale molecular simulation based on bond-order ReaxFF to simulate the chemical reaction and study the damage to a large fragment of DNA-molecule in the solution by ionizing radiation. We illustrate that the randomly distributed clusters of diatomic OH-radicals that are primary products of megavoltage ionizing radiation in water-based systems are the main source of hydrogen-abstraction as well as formation of carbonyl- and hydroxyl-groups in the sugar-moiety that create holes in the sugar-rings. These holes grow up slowly between DNA-bases and DNA-backbone and the damage collectively propagate to DNA single and double strand break.

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Ramin M. Abolfath, A. C. T. van Duin, Thomas Brabec. 2011-12-12. Reactive Molecular Dynamics study on the first steps of DNA-damage by free hydroxyl radicals. https://doi.org/10.1021/jp204894m

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