关键的结构图案平衡金属结合和氧化反应在异金属/铁蛋白中
Effie C Kisgeropoulos, Julia J Griese1,2, Zachary R Smith
1Department of Biochemistry and Biophysics, Stockholm University, SE-106 91 Stockholm, Sweden.
Journal of the American Chemical Society
|February 18, 2020
概括
异金属/铁 (Mn/Fe) 蛋白质挑战化学规范. 这项研究揭示了R2lox蛋白质.
科学领域:
- 生物有机化学 生物有机化学
- 蛋白质工程是指蛋白质工程.
- 生物物理化学 生物物理化学
背景情况:
- 异金属Mn/Fe蛋白质代表了一个新的辅因子类.
- 它们的活性部位组装与已经确立的化学原理如欧文-威廉姆斯系列相矛盾.
- 反应性和金属结合机制在很大程度上仍未被探索.
研究的目的:
- 为了研究Mn/Fe R2-样联结氧化酶 (R2lox) 蛋白中的组合和C-H键激活.
- 阐明结构-反应性关系,控制辅助因子的结合和功能.
- 了解对选择性金属结合的热力学控制.
主要方法:
- 使用了一套全面的生物物理技术.
- 包括时间分辨率光学光谱学,X射线晶体学和电子磁共振光谱学.
- 采用全球运动建模,蛋白质电化学和质谱仪进行详细分析.
主要成果:
- 证明选择性金属结合是热力学控制的,在阿波蛋白中对Mn{\displaystyle M_{\text{II}}比Fe{\text{II}}有更高的亲和力.
- 表明C-H键激活效率与Mn/Fe辅因子的减少潜力相关.
- 发现C-H键激活效率和双价金属结合亲和力之间存在反向关系.
结论:
- R2lox活性部位是精确调整为选择性异金属结合和高反应性.
- 蛋白质结构和金属还原潜力是C-H键激活效率的关键决定因素.
- 提供了对蛋白质实现特定金属结合的机制的见解.
更多相关视频
11:04Ion Mobility-Mass Spectrometry Techniques for Determining the Structure and Mechanisms of Metal Ion Recognition and Redox Activity of Metal Binding Oligopeptides
Published on: September 7, 2019
9.7K
05:35Quantification of Metal Leaching in Immobilized Metal Affinity Chromatography
Published on: January 17, 2020
7.9K
相关概念视频
02:51Metal-Ligand Bonds
23.5K
The hemoglobin in the blood, the chlorophyll in green plants, vitamin B-12, and the catalyst used in the manufacture of polyethylene all contain coordination compounds. Ions of the metals, especially the transition metals, are likely to form complexes.
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
23.5K
01:09Complexation Equilibria: Factors Influencing Stability of Complexes
723
In complexation reactions, metal cations are the electron pair acceptors, and the ligands are the electron pair donors. The stability of the metal complexes depends primarily on the complexing ability of the central metal ion and the nature of the ligands. Generally, the complexing ability of the metal ion depends on the size and charge of the ion. As the metal ion size increases, the stability of the metal complexes decreases, provided that the valency of the metal ion and the ligands remain...
723
02:42Valence Bond Theory
10.9K
Coordination compounds and complexes exhibit different colors, geometries, and magnetic behavior, depending on the metal atom/ion and ligands from which they are composed. In an attempt to explain the bonding and structure of coordination complexes, Linus Pauling proposed the valence bond theory, or VBT, using the concepts of hybridization and the overlapping of the atomic orbitals. According to VBT, the central metal atom or ion (Lewis acid) hybridizes to provide empty orbitals of suitable...
10.9K
01:19Complexation Equilibria: The Chelate Effect
1.0K
In complexation reactions, metal atoms or cations interact with ligands to form donor-acceptor adducts called metal complexes. Ligands that bind through one donor site are monodentate, ligands with two donor sites are bidentate, and those with more than two donor sites are polydentate ligands. For example, ethylene diamine is a bidentate ligand that binds through two nitrogen donor atoms, forming a five-membered ring. EDTA is a polydentate ligand that binds through four oxygen and two nitrogen...
1.0K
02:34Structural Isomerism
21.4K
Isomerism in Complexes
Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
Linkage isomers occur when the coordination compound contains a ligand that can bind to the transition metal center through two different atoms. For example, the CN− ligand can bind through the carbon atom or through the nitrogen atom. Similarly, SCN− can...
Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
Linkage isomers occur when the coordination compound contains a ligand that can bind to the transition metal center through two different atoms. For example, the CN− ligand can bind through the carbon atom or through the nitrogen atom. Similarly, SCN− can...
21.4K
03:02Colors and Magnetism
13.6K
Color in Coordination Complexes
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...
13.6K