Thermal Motion of DNA in an MspA Pore.

نویسندگان

  • Bo Lu
  • Stephen Fleming
  • Tamas Szalay
  • Jene Golovchenko
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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عنوان ژورنال:
  • Biophysical journal

دوره 109 7  شماره 

صفحات  -

تاریخ انتشار 2015