基于DNA的不对称催化:依赖序列的速率加速和反选择性
Arnold J Boersma1, Jaap E Klijn, Ben L Feringa
1Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, The Netherlands.
Journal of the American Chemical Society
|August 7, 2008
概括
DNA显著增强了迪尔斯-阿尔德反应,超出了简单的脚手架. 这种基于DNA的催化,使用铜复合体,显示了依赖序列的速率加速和酶选择性.
科学领域:
- 超分子化学 超分子化学
- 催化剂是一种催化剂.
- 有机化学 有机化学
背景情况:
- 在催化过程中,DNA的作用往往局限于一种性脚手架.
- 在有机合成中,具有酶选择性的迪尔斯-阿尔德反应至关重要.
- 铜复合体与双皮里丁配体是已知的催化剂.
研究的目的:
- 为了研究DNA在酶选择性迪尔斯-阿尔德反应中的作用,超出了性支架.
- 为了探索依赖DNA序列的催化.
- 为了展示混合催化剂的超分子方法.
主要方法:
- 基于DNA的催化利用鱼丸DNA和一个铜-双胺复合体 (Cu-L1).
- 迪尔斯-阿尔德反应在阿扎卡尔和环二烯之间.
- 对反应速率和酶选择性进行分析.
主要成果:
- DNA的作用不仅仅是性脚手架,能够显著加快速度 (高达2个数量级).
- 速率提升和酶选择性都取决于DNA序列.
- 通过鱼丸DNA/Cu-L1.1实现了高效和选择性催化.
结论:
- DNA可以积极参与催化,提供实质性的速度加速和enantiocontrol.
- DNA 序列是混合催化效率的关键因素.
- 这种超分子方法使用简单的DNA结合复合体展示了强大的立体控制.
相关概念视频
Reduction of Alkenes: Asymmetric Catalytic Hydrogenation
Catalytic hydrogenation of alkenes is a transition-metal catalyzed reduction of the double bond using molecular hydrogen to give alkanes. The mode of hydrogen addition follows syn stereochemistry.
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
Introduction to Mechanisms of Enzyme Catalysis
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 a mild...
Introduction to Mechanisms of Enzyme Catalysis
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 a mild...
Enzymes
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...
Enzyme Kinetics
Enzymes speed up reactions by lowering the activation energy of the reactants. The speed at which the enzyme turns reactants into products is called the rate of reaction. Several factors impact the rate of reaction, including the number of available reactants. Enzyme kinetics is the study of how an enzyme changes the rate of a reaction.
Scientists typically study enzyme kinetics with a fixed amount of enzyme in the controlled environment of a test tube. When more reactant, or substrate, is...
Scientists typically study enzyme kinetics with a fixed amount of enzyme in the controlled environment of a test tube. When more reactant, or substrate, is...
Catalytically Perfect Enzymes
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.


