2 research outputs found
Active translocation of a semiflexible polymer assisted by an ATP-based molecular motor
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.Comment: 10 pages, 10 figure
Translocation of a polymer chain driven by a dichotomous noise
We consider the translocation of a one-dimensional polymer through a pore
channel helped by a motor driven by a dichotomous noise with time exponential
correlation. We are interested in the study of the translocation time, mean
velocity and stall force of the system as a function of the mean driving
frequency. We find a monotonous translocation time, in contrast with the mean
velocity which shows a pronounced maximum at a given frequency. Interestingly,
the stall force shows a nonmonotonic behavior with the presence of a minimum.
The influence of the spring elastic constant to the mean translocation times
and velocities is also presented.Comment: 11 pages, 7 figure