Thermal Motion of DNA in an MspA Pore.
نویسندگان
چکیده
We report on an experiment and calculations that determine the thermal motion of a voltage-clamped single-stranded DNA-NeutrAvidin complex in a Mycobacterium smegmatis porin A nanopore. The electric force and diffusion constant of DNA inside a Mycobacterium smegmatis porin A pore were determined to evaluate the thermal position fluctuations of DNA. We show that an out-of-equilibrium state returns to equilibrium so quickly that experiments usually measure a weighted average over the equilibrium position distribution. Averaging over the equilibrium position distribution is consistent with results of state-of-the-art nanopore sequencing experiments. It is shown how a reduction in thermal position fluctuations can be achieved by increasing the electrophoretic force used in nanopore sequencing devices.
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ورودعنوان ژورنال:
- Biophysical journal
دوره 109 7 شماره
صفحات -
تاریخ انتشار 2015