LAMBE UMR CNRS 8587, Université d'Evry et de Cergy-Pontoise, France.
ACS Nano. 2011 May 24;5(5):3628-38. doi: 10.1021/nn1034795. Epub 2011 Apr 26.
We report experimentally the dynamic properties of the entry and transport of unfolded and native proteins through a solid-state nanopore as a function of applied voltage, and we discuss the experimental data obtained as compared to theory. We show an exponential increase in the event frequency of current blockades and an exponential decrease in transport times as a function of the electric driving force. The normalized current blockage ratio remains constant or decreases for folded or unfolded proteins, respectively, as a function of the transmembrane potential. The unfolded protein is stretched under the electric driving force. The dwell time of native compact proteins in the pore is almost 1 order of magnitude longer than that of unfolded proteins, and the event frequency for both protein conformations is low. We discuss the possible phenomena hindering the transport of proteins through the pores, which could explain these anomalous dynamics, in particular, electro-osmotic counterflow and protein adsorption on the nanopore wall.
我们实验报告了未折叠和天然蛋白质通过固态纳米孔的进入和传输的动力学特性，作为施加电压的函数，并讨论了与理论相比获得的实验数据。我们发现，电流阻断事件的频率随着电场驱动力的增加呈指数增长，而传输时间则呈指数下降。对于折叠或未折叠的蛋白质，归一化的电流阻断比分别保持不变或减小，这是作为跨膜电位的函数。未折叠的蛋白质在电场驱动力下被拉伸。天然紧凑蛋白质在孔中的停留时间比未折叠蛋白质长约 1 个数量级，并且两种蛋白质构象的事件频率都很低。我们讨论了可能阻碍蛋白质通过孔传输的现象，这些现象可以解释这些异常的动力学，特别是电动渗透逆流和蛋白质在纳米孔壁上的吸附。
