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تسجيل مستخدم جديدDynamics of DNA translocation through an attractive nanopore
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We investigate the dynamics of DNA translocation through a nanopore driven by an external force using Langevin dynamics simulations in two dimensions (2D) to study how the translocation dynamics depend on the details of the DNA sequences. We consider a coarse-grained model of DNA built from two bases $A$ and $C$, having different base-pore interactions, {textit e.g.}, a strong (weak) attractive force between the pore and the base $A$ ($C$) inside the pore. From a series of studies on hetero-DNAs with repeat units $A_mC_n$, we find that the translocation time decreases exponentially as a function of the volume fraction $f_C$ of the base $C$. %($epsilon_{pC} < epsilon_{pA}$). For longer $A$ sequences with $f_C le 0.5$, the translocation time strongly depends on the orientation of DNA, namely which base enters the pore first. Our studies clearly demonstrate that for a DNA of certain length $N$ with repeat units $A_mC_n$, the pattern exhibited by the waiting times of the individual bases and their periodicity can unambiguously determine the values of $m$, $n$ and $N$ respectively. Therefore, a prospective experimental realization of this phenomenon may lead to fast and efficient sequence detection technic.
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We investigate the dynamics of DNA translocation through a nanopore using 2D Langevin dynamics simulations, focusing on the dependence of the translocation dynamics on the details of DNA sequences. The DNA molecules studied in this work are built fro
m two types of bases $A$ and $C$, which has been shown previously to have different interactions with the pore. We study DNA with repeating blocks $A_nC_n$ for various values of $n$, and find that the translocation time depends strongly on the {em block length} $2n$ as well as on the {em orientation} of which base entering the pore first. Thus, we demonstrate that the measurement of translocation dynamics of DNA through nanopore can yield detailed information about its structure. We have also found that the periodicity of the block sequences are contained in the periodicity of the residence time of the individual nucleotides inside the pore.
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 $epsilon$ between the chaperone and the chain and the chaperone
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