First passage time distribution of chaperone driven polymer translocation through a nanopore: homopolymer and heteropolymer cases.
نویسندگان
چکیده
Combining the advection-diffusion equation approach with Monte Carlo simulations we study chaperone driven polymer translocation of a stiff polymer through a nanopore. We demonstrate that the probability density function of first passage times across the pore depends solely on the Péclet number, a dimensionless parameter comparing drift strength and diffusivity. Moreover it is shown that the characteristic exponent in the power-law dependence of the translocation time on the chain length, a function of the chaperone-polymer binding energy, the chaperone concentration, and the chain length, is also effectively determined by the Péclet number. We investigate the effect of the chaperone size on the translocation process. In particular, for large chaperone size, the translocation progress and the mean waiting time as function of the reaction coordinate exhibit pronounced sawtooth-shapes. The effects of a heterogeneous polymer sequence on the translocation dynamics is studied in terms of the translocation velocity, the probability distribution for the translocation progress, and the monomer waiting times.
منابع مشابه
Sequence dependence of the binding energy in chaperone-driven polymer translocation through a nanopore.
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 ...
متن کاملPolymer Translocation Through a Nanopore: A Geometry Dependence Study
The translocation of a single stranded nucleic acid polymer through a nanopore, by an external electric field applied across the pore, may be well described by a 1-D drift-diffusion model. Translocation times and velocities are calculated for a homopolymer driven through a nanopore, where the polymerpore interaction dominates the polymer dynamics. In this model a purely electrostatic polymer-po...
متن کاملChaperone-assisted translocation of a polymer through a nanopore.
Using Langevin dynamics simulations, we investigate the dynamics of chaperone-assisted translocation of a flexible polymer through a nanopore. We find that increasing the binding energy ε between the chaperone and the chain and the chaperone concentration N(c) can greatly improve the translocation probability. Particularly, with increasing the chaperone concentration a maximum translocation pro...
متن کاملChaperone-driven polymer translocation through nanopore: Spatial distribution and binding energy.
Chaperones are binding proteins working as a driving force in biopolymer translocation. They bind to the biopolymer near the pore and prevent its backsliding. Chaperones may have different spatial distributions. Recently, we showed the importance of their spatial distribution in translocation and its effects on the sequence dependency of the translocation time. Here we focus on homopolymers and...
متن کاملDirected motion emerging from two coupled random processes: translocation of a chain through a membrane nanopore driven by binding proteins.
We investigate the translocation of a stiff polymer consisting of M monomers through a nanopore in a membrane, in the presence of binding particles (chaperones) that bind onto the polymer, and partially prevent backsliding of the polymer through the pore. The process is characterized by the rates: k for the polymer to make a diffusive jump through the pore, q for unbinding of a chaperone, and t...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- The Journal of chemical physics
دوره 135 24 شماره
صفحات -
تاریخ انتشار 2011