预先组织的电场如何在催化循环中起作用? 氨酸基酶的情况
Wei Peng1, Shengheng Yan1, Xuan Zhang1
1State Key Laboratory of Physical Chemistry of Solid Surfaces and Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering and Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), Xiamen University, Xiamen 361005, People Republic of China.
Journal of the American Chemical Society
|October 25, 2022
概括
大自然使用内在电场 (IEF) 来加速具有挑战性的酶步骤. 在氨酸酸化酶中,IEF优化了I化合物形成,但减缓了产品酸化,作为智能试剂.
科学领域:
- 生物化学和分子生物学
- 计算化学
- 酶催化
背景情况:
- 酶利用内在电场 (IEF) 进行静电催化.
- IEF在多步酶反应中的确切作用尚不清楚.
- 氨酸氧酶 (TyrH) 催化必要的氧化反应.
研究的目的:
- 研究IEF对氨酸酶 (TyrH) 催化循环的影响.
- 阐明IEF如何调节酶催化中的特定反应步骤.
主要方法:
- 分子动力学 (MD) 模拟.
- 量子力学/分子力学 (QM/MM) 的计算.
- 分析TyrH的两个阶段的催化周期.
主要成果:
- TyrH中的IEF优化了O-O键异解以产生化合物I (Cpd I).
- 在第一阶段,甲基催化O-O异质化.
- 他的88介质质子合电子转移和氧气转移发生在第二阶段.
- IEF减缓了芳香化阶段 (产品形成).
结论:
- 在 TyrH 中的 IEF 选择性地增强了具有挑战性的步骤,例如 Cpd I 生成,而不是产品形成.
- IEFs作为"智能试剂"来调节酶反应.
- 这些发现对理解O2/H2O2依赖的金属酶具有广泛的影响.
相关概念视频
Introduction to Mechanisms of Enzyme Catalysis
8.4K
For many years, scientists thought that enzyme-substrate binding took place in a simple "lock-and-key" fashion. This model stated that the enzyme and substrate fit together perfectly in one instantaneous step. However, current research supports a more refined view scientists call induced fit. The induced-fit model expands upon the lock-and-key model by describing a more dynamic interaction between enzyme and substrate. As the enzyme and substrate come together, their interaction causes...
8.4K
Catalytically Perfect Enzymes
4.1K
The theory of catalytically perfect enzymes was first proposed by W.J. Albery and J. R. Knowles in 1976. These enzymes catalyze biochemical reactions at high-speed. Their catalytic efficiency values range from 108-109 M-1s-1. These enzymes are also called 'diffusion-controlled' as the only rate-limiting step in the catalysis is that of the substrate diffusion into the active site. Examples include triose phosphate isomerase, fumarase, and superoxide dismutase.
Most enzymes...
Most enzymes...
4.1K
Enzymes
82.2K
Inside living organisms, enzymes act as catalysts for many biochemical reactions involved in cellular metabolism. The role of enzymes is to reduce the activation energies of biochemical reactions by forming complexes with its substrates. The lowering of activation energies favor an increase in the rates of biochemical reactions.
Enzyme deficiencies can often translate into life-threatening diseases. For example, a genetic abnormality resulting in the deficiency of the enzyme G6PD...
Enzyme deficiencies can often translate into life-threatening diseases. For example, a genetic abnormality resulting in the deficiency of the enzyme G6PD...
82.2K
Introduction to Enzymes
19.1K
The use of enzymes by humans dates to 7000 BCE. Humans first used enzymes to ferment sugars and produce alcohol without knowing that this was an enzyme-catalyzed reaction. Wilhelm Kuhne coined the term 'enzyme' in 1877 from the Greek words ‘en’ meaning ‘in’ or ‘within’ and ‘zyme’ meaning ‘yeast.’
Most enzymes are proteins that speed up biochemical reactions without being consumed. Enzymes contain one or more active sites that...
Most enzymes are proteins that speed up biochemical reactions without being consumed. Enzymes contain one or more active sites that...
19.1K
Catalysis
27.3K
The presence of a catalyst affects the rate of a chemical reaction. A catalyst is a substance that can increase the reaction rate without being consumed during the process. A basic comprehension of a catalysts’ role during chemical reactions can be understood from the concept of reaction mechanisms and energy diagrams.
27.3K
Induced-fit Model
81.5K
Most chemical reactions in cells require enzymes—biological catalysts that speed up the reaction without being consumed or permanently changed. They reduce the activation energy needed to convert the reactants into products. Enzymes are proteins, that usually work by binding to a substrate—a reactant molecule that they act upon.
Enzymes exhibit substrate specificity, meaning that they can only bind to certain substrates. This is mainly determined by the shape and chemical...
Enzymes exhibit substrate specificity, meaning that they can only bind to certain substrates. This is mainly determined by the shape and chemical...
81.5K

![Protein Film Infrared Electrochemistry Demonstrated for Study of H2 Oxidation by a [NiFe] Hydrogenase](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F55858.jpg&w=3840&q=50)
