Automated quantum chemistry based molecular dynamics simulations of electron ionization induced fragmentations of the nucleobases uracil, thymine, cytosine, and guanine
Automated quantum chemistry based molecular dynamics simulations of electron ionization induced fragmentations of the nucleobases uracil, thymine, cytosine, and guanine
复制标题
DOI：
10.1255/ejms.1313
复制
发表时间：
2015-01-01
影响因子：
1.3
通讯作者：
Grimme, Stefan
中科院分区：
文献类型：
--
作者：
Bauer, Christoph Alexander;Grimme, Stefan
利用混合量子-经典分子动力学方法研究了尿嘧啶、胸腺嘧啶、胞嘧啶和鸟嘌呤等核碱基的电子电离（EI）诱导的阳离子自由基的气相分解途径.在计算中没有使用预先设想的碎裂通道。这些结果与这些重要生物分子的大量实验和理论数据相比较。与我们的随机和动态相结合的方法，人们可以在一个公正的方式访问的能量可用的分解机制。此外，我们能够分离胞嘧啶和鸟嘌呤的不同互变异构体的EI质谱。我们的方法（以前称为量子化学电子电离质谱）再现自由核碱基的实验质谱以及提供详细的机械洞察到高能单分子分解过程。
The gas-phase decomposition pathways of electron ionization (EI)-induced radical cations of the nucleobases uracil, thymine, cytosine, and guanine are investigated by means of mixed quantum-classical molecular dynamics. No preconceived fragmentation channels are used in the calculations. The results compare well to a plethora of experimental and theoretical data for these important biomolecules. With our combined stochastic and dynamic approach, one can access in an unbiased way the energetically available decomposition mechanisms. Additionally, we are able to separate the EI mass spectra of different tautomers of cytosine and guanine. Our method (previously termed quantum chemistry electron ionization mass spectra) reproduces free nucleobase experimental mass spectra well and provides detailed mechanistic in-sight into high-energy unimolecular decomposition processes.