酶的内在动力学是催化物的基础
Elan Z Eisenmesser1, Oscar Millet, Wladimir Labeikovsky
1Department of Biochemistry, Howard Hughes Medical Institute, Brandeis University, Waltham, Massachusetts 02454, USA.
Nature
|November 4, 2005
概括
酶催化依赖于蛋白质的灵活性. 研究表明,酶功能所需的运动是固有的,并且在自由酶中预先存在,可能会限制反应速度.
科学领域:
- 生物化学 生物化学
- 结构生物学 结构生物学
- 酶学 是一种酶学.
背景情况:
- 酶催化涉及在折叠的蛋白质中的反应性原子.
- 传统上,理解酶功能的重点是化学反应和静态结构.
- 人们越来越认识到蛋白质动态在酶催化中的作用.
研究的目的:
- 为了研究蛋白质灵活性和酶功能之间的联系.
- 在催化过程中描述prolyl cis-trans异构酶cyclophilin A (CypA) 的动态.
- 为了确定酶运动是否是固有的特性或是由基质结合引起的.
主要方法:
- 核磁共振 (NMR) 放松实验被用来研究CypA的动态.
- 对CypA.的无基质和催化活性状态的分析.
- 利用CypA的突变形式来调查集体动作.
主要成果:
- 在CypA.无基质状态中检测到对催化作用至关重要的酶运动.
- 这些运动的频率与催化剂的转换率相似.
- 蛋白质动态不仅限于活性部位,而是扩展到更广泛的网络,展示集体行为.
结论:
- 蛋白质可塑性和先前存在的集体动态是酶催化的主要特征.
- 这些内在运动可能会决定甚至限制酶的催化转换率.
- 酶进化可能涉及蛋白质结构和动态之间的协同压力.
相关概念视频
Induced-fit Model
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Enzymes exhibit substrate specificity, meaning that they can only bind to certain substrates. This is mainly determined by the shape and chemical characteristics of...
Enzymes exhibit substrate specificity, meaning that they can only bind to certain substrates. This is mainly determined by the shape and chemical characteristics of...
Enzymes
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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...
Introduction to Enzymes
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 bind the substrates and convert them into products. Many enzymes also...
Most enzymes are proteins that speed up biochemical reactions without being consumed. Enzymes contain one or more active sites that bind the substrates and convert them into products. Many enzymes also...
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 Enzymes
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 bind the substrates and convert them into products. Many enzymes also...
Most enzymes are proteins that speed up biochemical reactions without being consumed. Enzymes contain one or more active sites that bind the substrates and convert them into products. Many enzymes also...
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...


