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Updated: Jun 3, 2026

Membrane Transport Processes Analyzed by a Highly Parallel Nanopore Chip System at Single Protein Resolution
Published on: August 16, 2016
Sequence dependence of the binding energy in chaperone-driven polymer translocation through a nanopore
Rouhollah Haji Abdolvahab1, Mohammad Reza Ejtehadi, Ralf Metzler
1Physics Department, Sharif University of Technology, Tehran, Iran.
Abstract:
We study the translocation of stiff polymers through a nanopore, driven by the chemical-potential gradient exerted by binding proteins (chaperones) on the trans side of the pore. Bound chaperones prevent backsliding through the pore and, therefore, partially rectify the polymer passage. We show that the sequence of chain monomers with different binding affinity for the chaperones significantly affects the translocation dynamics. In particular, we investigate the effect of the nearest-neighbor adjacency probability of the two monomer types. Depending on the magnitude of the involved binding energies, the translocation speed may either increase or decrease with the adjacency probability. We determine the mean first passage time and show that, by tuning the effective binding energy, the motion changes continuously from purely diffusive to ballistic translocation.
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