Slow folding-unfolding kinetics of an octameric β-peptide bundle.
Slow folding-unfolding kinetics of an octameric β-peptide bundle.
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八聚体β-肽束的缓慢折叠-展开动力学。
DOI：
10.1021/cb400621y
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发表时间：
2014
影响因子：
4
通讯作者：
DeGrado,WilliamF
中科院分区：
文献类型：
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作者：
Montalvo,GerondaL;Gai,Feng;Roder,Heinrich;DeGrado,WilliamF
β-肽折叠体为研究骨架柔性对蛋白质折叠动力学的影响提供了有吸引力的框架。本文中，我们研究了β-肽Acid-1 Y，1的折叠-解折叠动力学，该β-肽在水溶液中折叠成八聚体束肽，其构象被称为14-螺旋。酸-1Y仅由β-氨基酸组成，其与α-氨基酸的不同之处在于骨架中添加了一个亚甲基。我们的目标是了解β-氨基酸中额外的自由度和增加的骨架柔性如何影响折叠动力学，并测量这种八聚体β-肽的折叠速率。之前，我们发现形成单体14-螺旋的单体β-肽的T-跳跃诱导的弛豫动力学发生在纳秒时间尺度上2，并且明显慢于类似的基于丙氨酸的α-螺旋肽。3此外，与类似的α-螺旋相比，弛豫速率对温度的依赖性较弱。在这里，我们发现八聚体β-肽的T-跳跃诱导的弛豫动力学发生在甚至更慢的时间尺度（分钟）上，并且解折叠弛豫速率显示出对温度的很大依赖性。这些差异表明β-肽二级和四级结构的折叠能量景观彼此明显不同，并且与它们的α-螺旋对应物也明显不同。
β-Peptide foldamers offer attractive frameworks for examining the effect of backbone flexibility on the dynamics of protein folding. Herein, we study the folding–unfolding kinetics of a β-peptide, Acid-1Y,1 which folds in aqueous solution into an octameric bundle of peptides in a conformation known as the 14-helix. Acid-1Y is comprised exclusively of β-amino acids, which differ from α-amino acids by the addition of a single methylene into the backbone. We aim to understand how the additional degree of freedom and increased backbone flexibility in the β-amino acid affect folding dynamics and to measure folding rates of this octameric β-peptide. Previously, we found that the T-jump induced relaxation kinetics of a monomeric β-peptide that forms a monomeric 14-helix occurred on the nanosecond time scale2 and were noticeably slower than a similar alanine-based α-helical peptide.3 Additionally, in comparison to similar α-helices, the relaxation rates showed a weaker dependence on temperature. Here, we find that the T-jump induced relaxation kinetics of the octameric β-peptide occurs on an even slower time scale (minutes) and the unfolding relaxation rates show a large dependence on temperature. These differences indicate that folding energy landscapes of β-peptide secondary and quaternary structure are markedly distinct from one another and also from their α-helical counterparts.
通过核磁共振波谱测定设计的肽α-1的二级结构
DOI：
--
发表时间：
1991
期刊：
影响因子：
--
作者：
D. Ciesla;D. Gilbert;J. Feigon
通讯作者：
J. Feigon
影响因子：
15
作者：
Petersson, E. James;Craig, Cody J.;Schepartz, Alanna
通讯作者：
Schepartz, Alanna
.alpha.1B（一种设计用于形成四螺旋束的肽）的结构特性表征
DOI：
--
发表时间：
1992
期刊：
影响因子：
--
作者：
J. Osterhout;T. Handel;G. Na;A. Toumadje;R. C. Long;P. Connolly;J. Hoch;W. Johnson;D. Live;W. DeGrado
通讯作者：
W. DeGrado