@article {236, title = {Ion Channels Made from a Single Membrane-Spanning DNA Duplex}, journal = {Nano Letters}, volume = {16}, year = {2016}, month = {06/2016}, pages = {4665--4669}, abstract = {

Due to their hollow interior, transmembrane channels are capable of opening up pathways for ions across lipid membranes of living cells. Here, we demonstrate ion conduction induced by a single DNA duplex that lacks a hollow central channel. Decorated with six porpyrin-tags, our duplex is designed to span lipid membranes. Combining electrophysiology measurements with all-atom molecular dynamics simulations, we elucidate the microscopic conductance pathway\ (see\ water channel\ trajectory, require login to nanoHUB). Ions flow (see ion transport\ trajectory)\ at the DNA-lipid interface as the lipid head groups tilt towards the amphiphilic duplex forming a toroidal pore filled with water and ions. Ionic current traces produced by the DNA-lipid channel show well-defined insertion steps, closures and gating similar to those observed for traditional protein channels or synthetic pores. Ionic conductances obtained through simulations and experiments are in excellent quantitative agreement. The conductance mechanism realized here, with the smallest possible DNA-based ion channel, offers a route to design a new class of synthetic ion channels with maximum simplicity.

}, doi = {10.1021/acs.nanolett.6b02039}, author = {Kerstin G{\"o}pfrich and Chen-Yu Li and Iwona Mames and Satya Prathyusha Bhamidimarri and Maria Ricci and Jejoong Yoo and Adam Mames and Alexander Ohmann and Mathias Winterhalter and Eugen Stulz and Aleksei Aksimentiev and Ulrich F Keyser} }