阿尔法螺旋中阿拉宁与甘氨酸对蛋白质稳定性的影响
L Serrano1, J L Neira, J Sancho
1MRC Unit for Protein Function and Design, MRC Centre, Hills Road, Cambridge CB2 2QH, UK.
Nature
|April 2, 1992
概括
蛋白质螺旋的稳定性取决于氨基酸的位置. 氨酸稳定了内部螺旋的位置,而甘氨酸在螺旋末端是首选的,挑战了普遍的螺旋形成倾向值.
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:
- 合理的蛋白质设计依赖于理解氨基酸螺旋形成倾向 (s值).
- 关于氨酸 (Ala) 和甘氨酸 (Gly) 的相对螺旋形成倾向存在重大争论.
研究的目的:
- 研究氨酸和甘氨酸对蛋白质螺旋稳定性的上下文依赖影响.
- 要确定每个氨基酸的通用s值是否适用于所有螺旋位置.
主要方法:
- 对巴纳酶突变体的实验分析.
- 基于不同螺旋位置 (顶部和内部) 的氨基酸替代的螺旋稳定性的评估.
主要成果:
- 阿拉与Gly对螺旋稳定的相对影响取决于位置.
- 甘氨酸在N端和C端螺旋顶处受到强烈的青.
- 氨酸稳定了内部螺旋相对于糖氨酸的位置,比0.42 kcalmol-1.1.
- 观察到的变化与溶剂可访问的疏水性表面积和溶剂-蛋白质键的变化相关.
结论:
- 对于每个氨基酸,单一的,普遍适用的s值是不有效的.
- 螺旋形成倾向受到局部序列上下文和螺旋内的位置的影响.
- 这些发现完善了我们对蛋白质折叠和稳定性的理解,以实现合理的蛋白质设计.
相关概念视频
Protein Organization
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Intact DNA strands can be found in fossils, while scientists sometimes struggle to keep RNA intact under laboratory conditions. The structural variations between RNA and DNA underlie the differences in their stability and longevity. Because DNA is double-stranded, it is inherently more stable. The single-stranded structure of RNA is less stable but also more flexible and can form weak internal bonds. Additionally, most RNAs in the cell are relatively short, while DNA can be up to 250 million...
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Intact DNA strands can be found in fossils, while scientists sometimes struggle to keep RNA intact under laboratory conditions. The structural variations between RNA and DNA underlie the differences in their stability and longevity. Because DNA is double-stranded, it is inherently more stable. The single-stranded structure of RNA is less stable but also more flexible and can form weak internal bonds. Additionally, most RNAs in the cell are relatively short, while DNA can be up to 250 million...
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The size effect explains the change in atomic size on acidity. When comparing the acids formed from elements that belong to the same column in the periodic table, their atomic sizes...
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The three sp2 orbitals of the carbonyl carbon form three σ bonds, one each with the carbonyl oxygen, the α carbon, and the heteroatom, whereas the other two sp2 orbitals of the carbonyl oxygen are occupied by the lone pairs. Further, the unhybridized p...
Carboxylic acid derivatives contain an acyl group attached to a heteroatom such as chlorine, oxygen, or nitrogen. The carbonyl carbon and oxygen are both sp2-hybridized with an unhybridized p orbital.
The three sp2 orbitals of the carbonyl carbon form three σ bonds, one each with the carbonyl oxygen, the α carbon, and the heteroatom, whereas the other two sp2 orbitals of the carbonyl oxygen are occupied by the lone pairs. Further, the unhybridized p...
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