由MeV离子诱导的孤立核基的延迟碎片化
T Nakao1, R Takasu1, H Tsuchida1,2
1Department of Nuclear Engineering, Kyoto University, Kyoto 615-8540, Japan.
The Journal of chemical physics
|August 1, 2024
概括
快速离子对气相核基的影响揭示了不同的碎片化模式. 新的方法估计了离子寿命,显示单电荷离子的持续时间比双电荷离子更长.
科学领域:
- 物理化学 物理化学
- 化学物理 化学物理
- 辐射化学 辐射化学
背景情况:
- 核基是DNA和RNA的基本组成部分.
- 了解它们对高能离子冲击的反应对于辐射生物学和材料科学至关重要.
- 以前的研究经常使用更简单的射弹,如电子或光子.
研究的目的:
- 在MeV能量离子辐射下研究气相核基 (腺素,关氨酸,细胞素,氨酸, uracil) 的解离.
- 为了比较来自碳和质子冲击的碎片化模式,以了解重离子效应.
- 为了识别和描述延迟的碎片化路径和离子寿命.
主要方法:
- 用MeV能量碳和质子离子对孤立的气相核基进行辐射.
- 分析碎片化模式和碎片对之间的相关性.
- 开发和应用一种新的方法来确定微通道板检测器中性碎片 (HCN) 的效率.
- 单电荷和双电荷中间离子的寿命估计.
主要成果:
- 对于碳离子与质子冲击,观察到明显的碎片化模式.
- 从单电荷和双电荷离子中确定了延迟的碎片化途径.
- 单电荷的C5H5N5+离子的寿命估计为0.87 ± 0.43μs (C+) 和0.67 ± 0.09μs (H+).
- 这些寿命大约比双电荷离子 (C5H5N52+) 的寿命大约一个数量级.
结论:
- 快速离子辐射诱导核基中复杂的解离动态.
- 单电荷核基离子的寿命比双电荷离子要长得多,影响了随后的碎片化.
- 开发的方法提供了一个新的工具,用于测量离子-分子反应中中性碎片的寿命.
更多相关视频
08:31Sample Preparation and Experimental Design for In Situ Multi-Beam Transmission Electron Microscopy Irradiation Experiments
Published on: June 27, 2022
1.7K
05:22Author Spotlight: Characterizing DNA Replication of Pathogenic Repeats to Uncover Mechanisms of Replication Fork Stalling and Expansion
Published on: September 13, 2024
718
相关概念视频
Mass Spectrometry: Molecular Fragmentation Overview
3.0K
The ionization of a molecule into a molecular ion inside the mass spectrometer causes instability in the molecule's structure due to the loss of an electron. This eventually leads to the fragmentation or breaking of some bonds in the molecule. The fragmentation occurs predominantly at specific bonds to yield relatively stable fragments.
One type of fragmentation pattern is the cleavage of a single bond in the molecular ion. The cleavage leads to a radical and a cation. The cleavage can...
One type of fragmentation pattern is the cleavage of a single bond in the molecular ion. The cleavage leads to a radical and a cation. The cleavage can...
3.0K
Long-patch Base Excision Repair
7.0K
Since the discovery of the two BER pathways, there has been a debate about how a cell chooses one pathway over the other and the factors determining this selection. Numerous in vitro experiments have pointed out multiple determinants for the sub-pathway selection. These are:
7.0K
Mismatch Repair
4.8K
Organisms are capable of detecting and fixing nucleotide mismatches that occur during DNA replication. This sophisticated process requires identifying the new strand and replacing the erroneous bases with correct nucleotides. Mismatch repair is coordinated by many proteins in both prokaryotes and eukaryotes.
The Mutator Protein Family Plays a Key Role in DNA Mismatch Repair
The human genome has more than 3 billion base pairs of DNA per cell. Prior to cell division, that vast amount of genetic...
The Mutator Protein Family Plays a Key Role in DNA Mismatch Repair
The human genome has more than 3 billion base pairs of DNA per cell. Prior to cell division, that vast amount of genetic...
4.8K
Nucleotide Excision Repair
37.0K
Overview
37.0K
Homologous Recombination
50.4K
The basic reaction of homologous recombination (HR) involves two chromatids that contain DNA sequences sharing a significant stretch of identity. One of these sequences uses a strand from another as a template to synthesize DNA in an enzyme-catalyzed reaction. The final product is a novel amalgamation of the two substrates. To ensure an accurate recombination of sequences, HR is restricted to the S and G2 phases of the cell cycle. At these stages, the DNA has been replicated already and the...
50.4K
Maxam-Gilbert Sequencing
11.1K
In the same year as the discovery of the Sanger sequencing method, another group of scientists, Allan Maxam and Walter Gilbert, demonstrated their chemical-cleavage method for DNA sequencing. The Maxam-Gilbert method relies on using different chemicals that can cleave the DNA sequence at specific sites, the separation of resulting DNA fragments of variable size using electrophoresis, and deciphering the DNA sequence from the resulting gel bands.
Challenges of the Maxam-Gilbert Method
The...
Challenges of the Maxam-Gilbert Method
The...
11.1K
