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Charge, Diffusion, and Current Fluctuations of Single-Stranded DNA Trapped in an MspA Nanopore.

ABSTRACT: We report effective charges and diffusion constants of several different single-stranded DNA oligonucleotides trapped in an MspA nanopore. Nucleotide identity is found to have a substantial influence on effective charges and diffusion constants. These quantities are determined from escape time experiments for a DNA molecule attached to a NeutrAvidin molecule that, unlike the DNA, does not pass through the pore. Correlations are reported between oligonucleotide effective charges and current blockages, and between their diffusion constants and DNA-induced current blockage fluctuations. We also report an unanticipated source of current fluctuations that reflects a discrete blockage current level structure. We posit that this is associated with interactions between the NeutrAvidin molecule and the MspA nanopore.

SUBMITTER: Fleming SJ

PROVIDER: S-EPMC5266147 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature

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Charge, Diffusion, and Current Fluctuations of Single-Stranded DNA Trapped in an MspA Nanopore.

Fleming Stephen J SJ Lu Bo B Golovchenko Jene A JA

Biophysical journal 20170101 2

We report effective charges and diffusion constants of several different single-stranded DNA oligonucleotides trapped in an MspA nanopore. Nucleotide identity is found to have a substantial influence on effective charges and diffusion constants. These quantities are determined from escape time experiments for a DNA molecule attached to a NeutrAvidin molecule that, unlike the DNA, does not pass through the pore. Correlations are reported between oligonucleotide effective charges and current block ...[more]

PMID: 28122222

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