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arXiv · 1705.05174

Active translocation of a semiflexible polymer assisted by an ATP-based molecular motor

A. Fiasconaro·J. J. Mazo·F. Falo
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Abstract

In this work we study the assisted translocation of a polymer across a membrane nanopore, inside which a molecular motor exerts a force fuelled by the hydrolysis of ATP molecules. In our model the motor switches to its active state for a fixed amount of time, while it waits for an ATP molecule binding and triggering the impulse, during an exponentially distributed time lapse. The polymer is modelled as a beads-springs chain with both excluded volume and bending contributions, and moves in a stochastic three dimensional environment modelled with a Langevin dynamics at fixed temperature. The resulting dynamics shows a Michaelis-Menten translocation velocity that depends on the chain flexibility. The scaling behavior of the mean translocation time with the polymer length for different bending values is also investigated.

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A. Fiasconaro, J. J. Mazo, F. Falo. 2017-05-15. Active translocation of a semiflexible polymer assisted by an ATP-based molecular motor. https://doi.org/10.1038/s41598-017-04364-7

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