Single-molecule protein sequencing is essential for a wide range of research and application fields, where the recently emerging 2D nanopores have open unprecedented possibilities. The protein translocating through a 2D nanopore plays vital roles in the nanopore-based analysis, where various detection or sequencing method could be employed. It is critically important to study the protein translocating through various 2D nanopores, which may help design efficient nanopore devices. However, few 2D materials other than graphene have been studied in this context yet. In this work, molecular dynamics (MD) simulations were employed to investigate the feasibility of single-molecule protein sequencing with a MoS₂ nanopore. Both phenylalanine–glycine repeat peptides and a peptide with the sequence taken from the thioredoxin protein were studied in their extended unfolded state, which adsorbed onto the MoS₂ membrane spontaneously. These peptides kept adsorbing onto MoS₂ and permeated unidirectionally through the MoS₂ nanopore, driven by either an electric field or hydrostatic pressure gradient. Their translocation process was stepwise, and the speed sensitively depended on the electric field, hydrostatic pressure, the charge density, or hydrophobicity of the peptides. The stepwise peptide translocation yielded ionic current blockades correlating with the sequence of peptide fragment in the nanopore. This work provides with insights for designing a protein-sequencing device with a MoS₂ nanopore.

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通过MoS ₂纳米孔的蛋白质易位：分子动力学研究

单分子蛋白质测序对于广泛的研究和应用领域至关重要，在这些领域中，最近出现的2D纳米孔具有前所未有的可能性。通过2D纳米孔转运的蛋白质在基于纳米孔的分析中起着至关重要的作用，其中可以采用各种检测或测序方法。研究蛋白质通过各种2D纳米孔的转运至关重要，这可能有助于设计高效的纳米孔设备。但是，在这种情况下，除了石墨烯以外，几乎没有研究2D材料。在这项工作中，采用分子动力学（MD）模拟来研究使用MoS ₂进行单分子蛋白质测序的可行性纳米孔。研究了苯丙氨酸-甘氨酸重复肽和具有从硫氧还蛋白蛋白中提取的序列的肽，它们处于展开的未折叠状态，并自发吸附在MoS ₂膜上。这些肽保持吸附在MoS _2上并单向渗透通过MoS ₂电场或流体静压力梯度驱动的纳米孔。它们的转运过程是逐步的，并且速度敏感地取决于电场，静水压力，电荷密度或肽的疏水性。逐步的肽移位产生与纳米孔中的肽片段的序列相关的离子电流阻滞。这项工作为设计具有MoS ₂纳米孔的蛋白质测序设备提供了见识。