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DNA-assisted oligomerization of pore-forming toxin monomers into precisely-controlled protein channels.

ABSTRACT: We have developed a novel approach for creating membrane-spanning protein-based pores. The construction principle is based on using well-defined, circular DNA nanostructures to arrange a precise number of pore-forming protein toxin monomers. We can thereby obtain, for the first time, protein pores with specifically set diameters. We demonstrate this principle by constructing artificial alpha-hemolysin (?HL) pores. The DNA/?HL hybrid nanopores composed of twelve, twenty or twenty-six monomers show stable insertions into lipid bilayers during electrical recordings, along with steady, pore size-dependent current levels. Our approach successfully advances the applicability of nanopores, in particular towards label-free studies of single molecules in large nanoscaled biological structures.

SUBMITTER: Henning-Knechtel A

PROVIDER: S-EPMC5716084 | biostudies-literature | 2017 Dec

REPOSITORIES: biostudies-literature

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DNA-assisted oligomerization of pore-forming toxin monomers into precisely-controlled protein channels.

Henning-Knechtel Anja A Knechtel Johann J Magzoub Mazin M

Nucleic acids research 20171201 21

We have developed a novel approach for creating membrane-spanning protein-based pores. The construction principle is based on using well-defined, circular DNA nanostructures to arrange a precise number of pore-forming protein toxin monomers. We can thereby obtain, for the first time, protein pores with specifically set diameters. We demonstrate this principle by constructing artificial alpha-hemolysin (αHL) pores. The DNA/αHL hybrid nanopores composed of twelve, twenty or twenty-six monomers sho ...[more]

PMID: 29088457

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