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Unzipping Kinetics of Double-Stranded DNA in a Nanopore

Alexis F. Sauer-Budge·Jacqueline A. Nyamwanda·David K. Lubensky·Daniel Branton
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Abstract

We studied the unzipping kinetics of single molecules of double-stranded DNA by pulling one of their two strands through a narrow protein pore. PCR analysis yielded the first direct proof of DNA unzipping in such a system. The time to unzip each molecule was inferred from the ionic current signature of DNA traversal. The distribution of times to unzip under various experimental conditions fit a simple kinetic model. Using this model, we estimated the enthalpy barriers to unzipping and the effective charge of a nucleotide in the pore, which was considerably smaller than previously assumed.

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Alexis F. Sauer-Budge, Jacqueline A. Nyamwanda, David K. Lubensky, Daniel Branton. 2003-05-02. Unzipping Kinetics of Double-Stranded DNA in a Nanopore. https://doi.org/10.1103/physrevlett.90.238101

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