一个局部的特定相互作用改变了结构同类的展开路径
Guoqiang Xu1, Mahesh Narayan, Igor Kurinov
1Laboratory of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853-1301, USA.
Journal of the American Chemical Society
|January 26, 2006
概括
牛胰腺核糖酶A中的单个氨基酸相互作用显著改变了蛋白质展开的途径. 这一发现有助于理解蛋白质折叠和预测蛋白质结构功能关系.
科学领域:
- 蛋白质的生物化学 蛋白质的生物化学
- 结构生物学是结构生物学.
- 生物物理学的生物物理.
背景情况:
- 减少展开的研究揭示了蛋白质原生状态的形成和稳定性至关重要的分子内相互作用.
- 了解蛋白质折叠途径对于预测蛋白质的行为和功能至关重要.
研究的目的:
- 为了研究不同降解性展开速率和途径之间的核糖核酶A及其同类物,onconase之间的分子基础.
- 确定调节蛋白质动态并影响展开行为的特定相互作用.
主要方法:
- 牛胰腺核糖酶A (Tyr92到Gly,Ala或Leu) 的局部定向突变发生.
- 分析晶体结构,包括温度因素.
- 突变结构的分子动力学模拟.
主要成果:
- 在核糖酶A中,Tyr92和Pro93之间的局部环叠相互作用被确定为关键的稳定因子.
- 在含有二硫化物键的循环中的这种相互作用调节了局部蛋白质动态.
- 调制增强了二硫化物键的降解易受性,改变了展开的路径.
结论:
- 与onconase相比,Tyr92-Pro93相互作用解释了Ribonuclease A的明显的还原性展开行为.
- 这些发现对蛋白质折叠研究,结构功能预测的折叠识别和蛋白质分解裂变部位预测有意义.
相关概念视频
Structural Isomerism
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 be...
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 be...
Ligand Binding and Linkage
Allosteric proteins have more than one ligand binding site; the binding of a ligand to any of these sites influences the binding of ligands to the other sites. When a protein is allosteric, its binding sites are called coupled or linked. In the case of enzymes, the site that binds to the substrate is known as the active site and the other site is known as the regulatory site. When a ligand binds to the regulatory site, this leads to conformational changes in the protein that can influence the...
Cooperative Allosteric Transitions
Cooperative allosteric transitions can occur in multimeric proteins, where each subunit of the protein has its own ligand-binding site. When a ligand binds to any of these subunits, it triggers a conformational change that affects the binding sites in the other subunits; this can change the affinity of the other sites for their respective ligands. The ability of the protein to change the shape of its binding site is attributed to the presence of a mix of flexible and stable segments in the...
Ligand Binding and Linkage
Allosteric proteins have more than one ligand binding site; the binding of a ligand to any of these sites influences the binding of ligands to the other sites. When a protein is allosteric, its binding sites are called coupled or linked. In the case of enzymes, the site that binds to the substrate is known as the active site and the other site is known as the regulatory site. When a ligand binds to the regulatory site, this leads to conformational changes in the protein that can influence the...
Cooperative Allosteric Transitions
Cooperative allosteric transitions can occur in multimeric proteins, where each subunit of the protein has its own ligand-binding site. When a ligand binds to any of these subunits, it triggers a conformational change that affects the binding sites in the other subunits; this can change the affinity of the other sites for their respective ligands. The ability of the protein to change the shape of its binding site is attributed to the presence of a mix of flexible and stable segments in the...
Cooperative Allosteric Transitions
Cooperative allosteric transitions can occur in multimeric proteins, where each subunit of the protein has its own ligand-binding site. When a ligand binds to any of these subunits, it triggers a conformational change that affects the binding sites in the other subunits; this can change the affinity of the other sites for their respective ligands. The ability of the protein to change the shape of its binding site is attributed to the presence of a mix of flexible and stable segments in the...


