弗拉介导的双氧化控制了一个酶的Favorskii类型的重排
Robin Teufel1, Akimasa Miyanaga1, Quentin Michaudel2
1Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California San Diego, La Jolla, California, 92093, USA.
Nature
|October 29, 2013
概括
这项研究揭示了细菌酶EncM使用一种新的flavin-N5-oxide中间体进行氧化,独立于典型的过氧类物种. 这种独特的机制促进了多基酸氧化和抗生素热素生物合成.
科学领域:
- 生物化学 生物化学
- 酶学 是一种酶学.
- 有机化学 有机化学
背景情况:
- 黄蛋白是关键的氧化还原催化剂,传统上认为单氧化酶使用过氧黄中间体进行基质氧化.
- 了解flavoenzyme催化物的精确机制对于酶工程和药物发现至关重要.
研究的目的:
- 阐明细菌酶EncM在抗生素素的生物合成中的催化机制.
- 为了研究flavin氧化还原状态在poly ((β-carbonyl) 基质的氧化-脱双氧化中的作用.
主要方法:
- 用基质模仿EncM的X射线晶体学.
- 同位素标记研究探测反应中间体.
- 生物化学测试以表征酶活性.
主要成果:
- EncM催化了一种脱氧氧化-脱的过程,不依赖于过氧黄.
- 确定了一个稳定的flavin-oxygenating物种,被提出为flavin-N5-oxide.
- 这种机制涉及一种罕见的Favorskii-type重组,这对热素生物合成至关重要.
结论:
- 这些发现揭示了EncM中以前未知的flavin redox生物化学.
- EncM的独特机制微调了flavin辅因子的反应性,以实现高效的聚基酸电循环.
- 这项工作扩大了已知的flavoenzyme催化策略的范围.
相关概念视频
Oxidation of Phenols to Quinones
4.6K
In the presence of oxidizing agents, phenols are oxidized to quinones. Quinones can be easily reduced back to phenols using mild reducing agents. The electron-donating hydroxyl group enhances the reactivity of the aromatic ring, enabling oxidation of the ring even in the absence of an α hydrogen.
o-hydroxy phenols are oxidized to o-quinones and p-hydroxy phenols to p-quinones. Such redox reactions involve the transfer of two electrons and two protons. The reversible redox...
o-hydroxy phenols are oxidized to o-quinones and p-hydroxy phenols to p-quinones. Such redox reactions involve the transfer of two electrons and two protons. The reversible redox...
4.6K
Woodward–Hoffmann Selection Rules and Microscopic Reversibility
2.2K
Electrocyclic reactions, cycloadditions, and sigmatropic rearrangements are concerted pericyclic reactions that proceed via a cyclic transition state. These reactions are stereospecific and regioselective. The stereochemistry of the products depends on the symmetry characteristics of the interacting orbitals and the reaction conditions. Accordingly, pericyclic reactions are classified as either symmetry-allowed or symmetry-forbidden. Woodward and Hoffmann presented the selection criteria for...
2.2K
E2 Reaction: Kinetics and Mechanism
10.2K
SN2 substitutions and E2 eliminations of alkyl halides proceed via a concerted pathway. While the nucleophile attacks the alpha carbon in SN2 reactions, it functions as a strong base and abstracts a beta hydrogen in the E2 mechanism. The rate-limiting transition state in E2 elimination reactions is characterized by partially broken carbon–hydrogen and carbon–halogen bonds and a partially formed pi bond between the alpha and beta carbons. The beta hydrogen and halide are eliminated...
10.2K
Oxidation of Alkenes: Anti Dihydroxylation with Peroxy Acids
6.2K
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.
6.2K
Oxidation-Reduction Reactions
58.9K
Oxidation–Reduction Reactions
58.9K
Redox Reactions
1.2K
Redox reactions are vital biochemical processes that underpin energy metabolism in cells. These reactions involve the transfer of electrons between molecules, occurring in tandem as oxidation and reduction. Oxidation refers to the loss of electrons, while reduction denotes their gain. This coupling ensures the seamless flow of electrons through metabolic pathways. For example, in bacterial metabolism, glucose undergoes oxidation to carbon dioxide, while oxygen is simultaneously reduced to...
1.2K


