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Large-Conductance Transmembrane Porin Made from DNA Origami.

ABSTRACT: DNA nanotechnology allows for the creation of three-dimensional structures at nanometer scale. Here, we use DNA to build the largest synthetic pore in a lipid membrane to date, approaching the dimensions of the nuclear pore complex and increasing the pore-area and the conductance 10-fold compared to previous man-made channels. In our design, 19 cholesterol tags anchor a megadalton funnel-shaped DNA origami porin in a lipid bilayer membrane. Confocal imaging and ionic current recordings reveal spontaneous insertion of the DNA porin into the lipid membrane, creating a transmembrane pore of tens of nanosiemens conductance. All-atom molecular dynamics simulations characterize the conductance mechanism at the atomic level and independently confirm the DNA porins' large ionic conductance.

SUBMITTER: Gopfrich K

PROVIDER: S-EPMC5043419 | biostudies-literature | 2016 Sep

REPOSITORIES: biostudies-literature

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Large-Conductance Transmembrane Porin Made from DNA Origami.

Göpfrich Kerstin K Li Chen-Yu CY Ricci Maria M Bhamidimarri Satya Prathyusha SP Yoo Jejoong J Gyenes Bertalan B Ohmann Alexander A Winterhalter Mathias M Aksimentiev Aleksei A Keyser Ulrich F UF

ACS nano 20160823 9

DNA nanotechnology allows for the creation of three-dimensional structures at nanometer scale. Here, we use DNA to build the largest synthetic pore in a lipid membrane to date, approaching the dimensions of the nuclear pore complex and increasing the pore-area and the conductance 10-fold compared to previous man-made channels. In our design, 19 cholesterol tags anchor a megadalton funnel-shaped DNA origami porin in a lipid bilayer membrane. Confocal imaging and ionic current recordings reveal sp ...[more]

PMID: 27504755

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