Microsecond protein dynamics observed at the single-molecule level.
Microsecond protein dynamics observed at the single-molecule level.
复制标题
DOI：
10.1038/ncomms8685
复制
发表时间：
2015-07-07
影响因子：
16.6
通讯作者：
Tahara T
中科院分区：
文献类型：
--
作者：
Otosu T;Ishii K;Tahara T
多肽链如何获得特定的构象以实现独特的生物功能是蛋白质科学的中心问题。单分子光谱学与荧光共振能量转移相结合，被用来研究蛋白质在亚毫秒到秒的时间尺度上的构象异质性和状态到状态的转变动力学。然而，在微秒时间尺度上观察动力学仍然是非常具有挑战性的。这个时间尺度很重要，因为蛋白质动力学的基本过程发生了，实验和模拟之间的直接比较是可能的。在这里，我们报道了一种新的单分子技术，通过荧光寿命的关联来揭示蛋白质的微秒结构动力学。应用二维荧光寿命关联光谱方法研究了细胞色素c的构象动力学，从关联信号中指出了三个构象系综和每个系综中的微秒跃迁，说明了量化蛋白质微秒动力学在折叠自由能图景中的重要性。单分子光谱学可以在亚毫秒的时间尺度上可视化蛋白质构象的动态变化。在这里，Otosu等人。应用二维荧光寿命相关光谱在微秒时间尺度上可视化细胞色素c的七种构象之间的动力学。
How polypeptide chains acquire specific conformations to realize unique biological functions is a central problem of protein science. Single-molecule spectroscopy, combined with fluorescence resonance energy transfer, is utilized to study the conformational heterogeneity and the state-to-state transition dynamics of proteins on the submillisecond to second timescales. However, observation of the dynamics on the microsecond timescale is still very challenging. This timescale is important because the elementary processes of protein dynamics take place and direct comparison between experiment and simulation is possible. Here we report a new single-molecule technique to reveal the microsecond structural dynamics of proteins through correlation of the fluorescence lifetime. This method, two-dimensional fluorescence lifetime correlation spectroscopy, is applied to clarify the conformational dynamics of cytochrome c. Three conformational ensembles and the microsecond transitions in each ensemble are indicated from the correlation signal, demonstrating the importance of quantifying microsecond dynamics of proteins on the folding free energy landscape. Single molecule spectroscopy can visualise dynamic changes in protein conformation on the submillisecond timescale. Here, Otosu et al. apply two-dimensional fluorescence lifetime correlation spectroscopy to visualise dynamics between seven conformers of cytochrome c on the microsecond timescale.