在交替GC双链寡核酸中,基基与单电子氧化反应:一种新型的电子孔稳定
Annalisa Masi1, Amedeo Capobianco2, Krzysztof Bobrowski3
1Istituto per la Sintesi Organica e la Fotoreattività, Consiglio Nazionale delle Ricerche, 40129 Bologna, Italy.
Biomolecules
|October 28, 2023
概括
基基 (HO•) 和硫酸盐基离子 (SO4•−) 与富含GC的DNA发生反应. 这些反应形成了独特的中间物种,揭示了DNA序列中电子孔稳定的新机制.
科学领域:
- 化学生物学 化学生物学
- 辐射化学 辐射化学
- 分子生物学分子生物学
背景情况:
- 基基 (HO•) 和硫酸盐基离子 (SO4•−) 是辐射化学中的关键反应物种.
- 氧化氧核酸 (ODN) 容易受到这些激素的损伤.
- 了解DNA的激进反应对于放射生物学和纳米医学至关重要.
研究的目的:
- 研究HO•和SO4•−与交替的GC双链寡度氧核酸 (ds-ODN) 的反应机制.
- 用脉冲放射溶解来描述这些反应中形成的中间物种.
- 阐明DNA序列和结构在激素诱导损伤和修复途径中的作用.
主要方法:
- 脉冲放射溶解被用来产生短暂物种并获得光学光谱和动力数据 (ns到ms).
- 密度函数理论 (DFT) 对结构和时间依赖的DFT进行了计算,用于光谱分析.
- 这项研究重点关注的是palindromic 5'-d(GCGCGC) - 3' ds-ODN 和更短的 5'-d(GCGC) - 3' 序列.
主要成果:
- HO•加于G:C对形成一个可检测的[8-HO-G:C]• adduct.
- ds-ODN 的单电子氧化光谱被分配给去质子化的[G(-H+):C]•物种.
- 对于5'-d(GCGCGC) -3' ds-ODN,观察到一种不同的过渡物种,被分配为[G:C/C:G]•+,这表明电子孔在堆叠的基对上移位.
- 这种非本地化物种随后被水合到[8-HO-G:C]• adduct.
结论:
- 在ds-ODN中交替的GC序列使得通过移位实现电子孔稳定的一种新机制成为可能.
- 这些发现提供了对辐射诱导的DNA损伤和潜在的修复机制的初步步骤的见解.
- 这项工作促进了对基因相互作用与结构化核酸序列的理解.
更多相关视频
12:15Quantification of three DNA Lesions by Mass Spectrometry and Assessment of Their Levels in Tissues of Mice Exposed to Ambient Fine Particulate Matter
Published on: May 29, 2019
8.7K
14:12HPLC Measurement of the DNA Oxidation Biomarker, 8-oxo-7,8-dihydro-2’-deoxyguanosine, in Cultured Cells and Animal Tissues
Published on: August 1, 2015
27.2K
相关概念视频
01:11Radical Reactivity: Overview
2.1K
Radicals, the highly reactive species, gain stability by undergoing three different reactions. The first reaction involves a radical-radical coupling, in which a radical combines with another radical, forming a spin‐paired molecule. The second reaction is between a radical and a spin‐paired molecule, generating a new radical and a new spin‐paired molecule. The third reaction is radical decomposition in a unimolecular reaction, forming a new radical and a spin‐paired...
2.1K
02:04Oxidation of Alkenes: Anti Dihydroxylation with Peroxy Acids
5.9K
Diols are compounds with two hydroxyl groups. In addition to syn dihydroxylation, diols can also be synthesized through the process of anti dihydroxylation. The process involves treating an alkene with a peroxycarboxylic acid to form an epoxide. Epoxides are highly strained three-membered rings with oxygen and two carbons occupying the corners of an equilateral triangle. This step is followed by ring-opening of the epoxide in the presence of an aqueous acid to give a trans diol.
5.9K
01:02Radical Reactivity: Electrophilic Radicals
1.9K
Radicals adjacent to electron‐withdrawing groups are called electrophilic radicals. These radicals readily react with nucleophilic alkenes. For example, the malonate radical, in which the radical center is flanked by two electron‐withdrawing groups, reacts readily with butyl vinyl ether, which consists of an electron‐donating oxygen substituent. The reaction between electrophilic malonate radical and nucleophilic vinyl ether is favored because the radical has a...
1.9K
00:54Radical Formation: Homolysis
3.6K
A bond is formed between two atoms by sharing two electrons. When this bond is broken by supplying sufficient energy, either two electrons can be taken up by one atom forming ions by the cleavage called heterolysis, or the two electrons are shared by two atoms, with one each creating radicals by the cleavage called homolysis.
3.6K
01:23Reactivity of Enolate Ions
2.5K
Enolate ions are formed by the acid–base reaction of a carbonyl compound with a base. This leads to deprotonation of the α hydrogen atom, leading to a resonance-stabilized enolate ion where one of the contributing structures is an oxyanion, which imparts additional stability. Therefore, the proton on the α carbon is more acidic in nature than that of other sp3-hybridized C–H bonds but less acidic than those in O–H bonds where the negative charge in the conjugate...
2.5K
01:20Radical Autoxidation
2.2K
The oxidation of an organic compound in the presence of air or oxygen is called autoxidation. For example, cumene reacts with oxygen to form hydroperoxide. Autoxidation involves initiation, propagation, and termination steps. Many organic compounds are susceptible to autoxidation—especially ethers in the presence of oxygen, which form hydroperoxides. Even though this reaction is slow, old ether bottles contain small amounts of peroxide, which leads to laboratory explosions during ether...
2.2K