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bioRxiv · 10.1101/221457

Dynamics of a Form-Fitting Protein in a Nanopore: Avidin in ClyA

Lu, B.·Stokes, C.·Fahie, M.·Chen, M.·Golovchenko, J. A.·Hau, L. V.
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Abstract

We probe the molecular dynamics of a protein, avidin, as it is captured and trapped in a nanopore, ClyA, with time-resolved single-molecule electrical conductance measurements, and we present a method for visualizing this process from the data. The case of avidin in ClyA has rich time-dependent conductance spectra of discrete levels that correlate with different configurations of the protein in the pore. One is very long-lasting, stable and noise-free, and portends the use of this system as a platform for more general studies of proteins and other molecules, where avidin acts as a shuttle that ferries analytes into the pore for probing. We demonstrate this by the sensitive detection of a biotin molecule attached to avidin captured by the pore. We also present an approach to determining the nanopore size based on a 3D printed model of the pore.

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Lu, B., Stokes, C., Fahie, M., Chen, M., Golovchenko, J. A., Hau, L. V.. 2017-11-17. Dynamics of a Form-Fitting Protein in a Nanopore: Avidin in ClyA. https://doi.org/10.1101/221457

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