n --> pi* 相互作用和n) ((pi保利排斥对蛋白质稳定性是对抗性的
Charles E Jakobsche1, Amit Choudhary, Scott J Miller
1Department of Chemistry, Yale University, New Haven, Connecticut 06520, USA.
Journal of the American Chemical Society
|April 28, 2010
概括
保利排斥可以防止相邻的碳基团在蛋白质中过于接近,而不会产生n --> pi*相互作用. 这就解释了为什么许多类模拟剂无法准确模仿蛋白质结构.
科学领域:
- 生物化学 生物化学
- 量子化学 是一个量子化学.
- 结构生物学 结构生物学
背景情况:
- 常见的蛋白质二次结构,如α螺旋体,具有相邻的骨干胺基碳基组.
- 一个n --> pi*相互作用促进了这些碳基的近距离,类似于伯吉-杜尼茨轨迹.
研究的目的:
- 为了研究邻近的胺碳基组之间的保利排斥的构造效应.
- 了解n --> pi*相互作用在维护蛋白质二次结构中的作用.
主要方法:
- 利用常见的模仿药来减弱n --> pi*相互作用,同时保持保利排斥.
- 分析了这些修饰结构的构造结果.
主要成果:
- 发现保利排斥在n --> pi*相互作用不存在时可以防止碳基基组的近位排列.
- 缺乏n --> pi*相互作用能力的类仿真药显示出胺键的模仿性较差.
结论:
- 许多类模拟剂无法参与n --> pi*相互作用,这导致它们在模拟胺基键方面失败.
- 蛋白质中相邻的胺基碳基组之间的相互作用基本上是量子力学.
相关概念视频
Protein Denaturation
The function of proteins depends on their native three-dimensional structure, which is dictated by the amino acid sequence of the specific protein. Folding of the polypeptide chain takes place under specific conditions that energetically favor the folded conformation. In contrast, protein denaturation occurs spontaneously under unfavorable conditions that disrupt the integrity of the folded conformation. Thus, the chemical and physical environment of a protein, such as significant changes in pH...
Protein Folding
Overview
Protein Folding
Proteins are chains of amino acids linked together by peptide bonds. Upon synthesis, a protein folds into a three-dimensional conformation, critical to its biological function. Interactions between its constituent amino acids guide protein folding, and hence the protein structure is primarily dependent on its amino acid sequence.
Protein Structure Is Critical to Its Biological Function
Proteins perform a wide range of biological functions such as catalyzing chemical reactions, providing...
Protein Structure Is Critical to Its Biological Function
Proteins perform a wide range of biological functions such as catalyzing chemical reactions, providing...
The Pauli Exclusion Principle
The arrangement of electrons in the orbitals of an atom is called its electron configuration. We describe an electron configuration with a symbol that contains three pieces of information:
Protein-protein Interfaces
Many proteins form complexes to carry out their functions, making protein-protein interactions (PPIs) essential for an organism's survival. Most PPIs are stabilized by numerous weak noncovalent chemical forces. The physical shape of the interfaces determines the way two proteins interact. Many globular proteins have closely-matching shapes on their surfaces, which form a large number of weak bonds. Additionally, many PPIs occur between two helices or between a surface cleft and a polypeptide...
Interpreting ¹H NMR Signal Splitting: The (n + 1) Rule
In the AX proton spin system, proton A can sense the two spin states of a coupled proton X, resulting in a doublet NMR signal with two peaks of equal (1:1) intensity. When proton A is coupled to two equivalent protons (AX2 spin system), the spin states of each X can be aligned with or against the external field, creating three possible scenarios. This results in a 1:2:1 triplet signal, where the central peak corresponds to the chemical shift of A and is twice as large or intense as the others.


