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Unfoldase-mediated protein translocation through an ?-hemolysin nanopore.

ABSTRACT: Using nanopores to sequence biopolymers was proposed more than a decade ago. Recent advances in enzyme-based control of DNA translocation and in DNA nucleotide resolution using modified biological pores have satisfied two technical requirements of a functional nanopore DNA sequencing device. Nanopore sequencing of proteins was also envisioned. Although proteins have been shown to move through nanopores, a technique to unfold proteins for processive translocation has yet to be demonstrated. Here we describe controlled unfolding and translocation of proteins through the ?-hemolysin (?-HL) pore using the AAA+ unfoldase ClpX. Sequence-dependent features of individual engineered proteins were detected during translocation. These results demonstrate that molecular motors can reproducibly drive proteins through a model nanopore--a feature required for protein sequence analysis using this single-molecule technology.

SUBMITTER: Nivala J

PROVIDER: S-EPMC3772521 | biostudies-literature | 2013 Mar

REPOSITORIES: biostudies-literature

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Unfoldase-mediated protein translocation through an α-hemolysin nanopore.

Nivala Jeff J Marks Douglas B DB Akeson Mark M

Nature biotechnology 20130203 3

Using nanopores to sequence biopolymers was proposed more than a decade ago. Recent advances in enzyme-based control of DNA translocation and in DNA nucleotide resolution using modified biological pores have satisfied two technical requirements of a functional nanopore DNA sequencing device. Nanopore sequencing of proteins was also envisioned. Although proteins have been shown to move through nanopores, a technique to unfold proteins for processive translocation has yet to be demonstrated. Here ...[more]

PMID: 23376966

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