Large-Conductance Transmembrane Porin Made from DNA Origami
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 tenfold compared to previous man-made channels. In our design, nineteen cholesterol-tags anchor a megadalton funnel-shaped DNA origami porin in a lipid bilayer membrane (see equilibration trajectory, require login to nanoHUB). 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 (see ionic current trajectory). All-atom molecular dynamics simulations characterize the conductance mechanism at the atomic level and independently confirm the DNA porins' large ionic conductance.