Dynamics of DNA molecules in a membrane channel probed by active control techniques
Dynamics of DNA molecules in a membrane channel probed by active control techniques
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DOI：
10.1016/s0006-3495(03)75042-5
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发表时间：
2003-04-01
影响因子：
3.4
通讯作者：
Meller, A
中科院分区：
文献类型：
--
作者：
Bates, M;Burns, M;Meller, A
在单分子水平上研究了α-溶血素蛋白孔中单链DNA的动力学。在没有外部施加电场的情况下测量最初被吸入孔中的 DNA 分子的逃逸时间。这些测量揭示了两个分离良好的时间尺度，其中一个时间尺度出人意料地长（大约毫秒）。我们将长时间尺度描述为与孔中 DNA 的结合和解离有关。我们还发现，小至 20 mV 的跨膜电位会强烈偏向 DNA 从孔中逃逸。这些实验之所以成为可能，是因为反馈控制系统的发展，允许快速调节孔内单个 DNA 分子所施加的力。
The dynamics of single-stranded DNA in an a-Hemolysin protein pore was studied at the single-molecule level. The escape time for DNA molecules initially drawn into the pore was measured in the absence of an externally applied electric field. These measurements revealed two well-separated timescales, one of which is surprisingly long (on the order of milliseconds). We characterized the long timescale as being associated with the binding and unbinding of DNA from the pore. We have also found that a transmembrane potential as small as 20 mV strongly biased the escape of DNA from the pore. These experiments have been made possible due to the development of a feedback control system, allowing the rapid modulation of the applied force on individual DNA molecules while inside the pore.