Institute for Materials Science and Max Bergmann Center of Biomaterials, Dresden University of Technology, 01062 Dresden, Germany.
J Phys Chem B. 2012 Sep 13;116(36):10977-85. doi: 10.1021/jp2091544. Epub 2012 Sep 4.
We present a detailed study of the charge transport characteristics of double-stranded DNA oligomers including the oxidative damage 7,8-dihydro-8-oxoguanine (8-oxoG). The problem is treated by a hybrid methodology combining classical molecular dynamics simulations and semiempirical electronic structure calculations to formulate a coarse-grained charge transport model. The influence of solvent- and DNA-mediated structural fluctuations is encoded in the obtained time series of the electronic charge transfer parameters. Within the Landauer approach to charge transport, we perform a detailed analysis of the conductance and current time series obtained by sampling the electronic structure along the molecular dynamics trajectory, and find that the inclusion of 8-oxoG damages into the DNA sequence can induce a change in the electrical response of the system. However, solvent-induced fluctuations tend to mask the effect, so that a detection of such sequence modifications via electrical transport measurements in a liquid environment seems to be difficult to achieve.
我们对双链 DNA 寡聚物的电荷输运特性进行了详细研究，其中包括氧化损伤 7,8-二氢-8-氧鸟嘌呤（8-oxoG）。该问题通过结合经典分子动力学模拟和半经验电子结构计算的混合方法来处理，以制定一个粗粒电荷输运模型。溶剂和 DNA 介导的结构波动的影响被编码在获得的电子电荷转移参数的时间序列中。在电荷输运的 Landauer 方法中，我们对沿分子动力学轨迹采样电子结构获得的电导和电流时间序列进行了详细分析，发现将 8-oxoG 损伤引入 DNA 序列会引起系统电响应的变化。然而，溶剂诱导的波动往往会掩盖这种影响，因此在液体环境中通过电输运测量来检测这种序列修饰似乎很难实现。
