Dissociative Electron Attachment to Biomolecules
Dissociative Electron Attachment to Biomolecules
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DOI：
10.1007/978-3-319-43030-0_5
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发表时间：
2017
期刊：
影响因子：
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通讯作者：
I. Bald;R. Čurík;J. Kopyra;M. Tarana
中科院分区：
文献类型：
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作者：
I. Bald;R. Čurík;J. Kopyra;M. Tarana
期间 的 最后 两 几十年来，人们已经清楚地认识到，由高能辐射引起的生物细胞损伤的很大一部分实际上是由于低能电子（<20 eV）引起的反应。在这种能量状态下，电子可以通过解离电子附着（DEA）有效地分解分子，如DNA或DNA构建块。 .在气相中对单个DNA结构单元进行的实验表明，DEA可以进行显着的位点选择性。低能电子诱导的DNA链断裂通常使用凝聚相中的质粒DNA进行研究。最近，使用不同的实验方法发现了电子诱导的DNA链断裂对核苷酸序列的显著依赖性，这表明至少部分观察到的链断裂是由于初始电子附着到核碱基 .目前，一个强有力的研究重点是对DEA的基本理解，以治疗放射增敏剂。在不久的将来，新的潜在的放射增敏剂的DEA将被探索，并在复杂的环境中的电子诱导的生物分子的损伤进行了研究。DNA损伤背景下的DEA理论研究一直受到人们的关注。关于这一点，本章的理论部分回顾了在过去十年中用于研究DEA对生物分子的所有计算方法。这些方法分为两类。第一类是电子结构方法 研究由DNA的中性构建块捕获的电子形成的瞬时负离子。处理DEA对生物分子的复杂核动力学的方法形成了本章探讨的第二类。
During the last two decades it became clear that a significant fraction of the biological cellular damage caused by high-energy radiation is actually due to reactions induced by low-energy electrons (<20 eV). In this energy regime electrons can efficiently decompose molecules such as DNA or DNA building blocks by dissociative electron attachment (DEA) . Experiments on single DNA building blocks have been performed in the gas phase revealing that DEA can proceed with remarkable site selectivity. Low-energy electron-induced DNA strand breakage is typically investigated using plasmid DNA in the condensed phase. Very recently, a pronounced dependence of electron induced DNA strand breakage on the nucleotide sequence was found using different experimental approaches suggesting that at least part of the observed strand breaks are due to initial electron attachment to the nucleobases . Currently, a strong research focus is on the fundamental understanding of DEA to therapeutically administered radiosensitizers. In the near future DEA to novel potential radiosensitizers will be explored, and the electron induced damage of biomolecules within complex environments has to be investigated. Considerable attention has been paid to the theoretical research of the DEA in the context of the DNA damage. With respect to this, the theoretical part of the chapter reviews all the computational approaches that have been used to study DEA to biomolecules over the last decade. These approaches are divided into two classes. The first class consists of electronic structure methods studying the transient negative ions formed by electrons captured by the neutral building blocks of the DNA. Approaches dealing with the complicated nuclear dynamics of the DEA to biomolecules form the second class explored in this chapter.