title: Transport at the nanoscale: temperature dependence of ion conductance.
abstract: Temperature dependent ion conductance in nanopores is measured in a wide range of electrolyte concentrations and compared with molecular modeling. Single outer membrane protein F (OmpF) channels from E. coli are reconstituted into planar lipid bilayers. In qualitative agreement with the experimental data, applied-field molecular dynamics unraveled atomistic details of the ion transport. Comparing the temperature dependence of the channel conductance with that of the bulk conductivity in the range from 0 to 90 degrees C revealed that at low salt concentrations the transport is mainly driven along the pore surface. Increasing the salt concentration saturates the surface charge transport and induces ion transport in the center of the nanopore. The confinement of the nanopore then favors the formation of ion pairs. Stepping up the temperature reduces the life time of the ion pairs and increases the channel conductance more than expected from the bulk behavior.
authors: School of Engineering and Science, Jacobs University Bremen, Campus Ring 1, Bremen, Germany.
authors: Catalin
authors: C
authors: Chimerel
authors: Liviu
authors: L
authors: Movileanu
authors: Soroosh
authors: S
authors: Pezeshki
authors: Mathias
authors: M
authors: Winterhalter
authors: Ulrich
authors: U
authors: Kleinekathöfer
mesh_terms: D004553:Electric Conductivity; D006863:Hydrogen-Ion Concentration; D015640:Ion Channel Gating; D008051:Lipid Bilayers / Q000737:chemistry*; D049329:Nanostructures / Q000737:chemistry*; D018272:Porins / Q000737:chemistry*; D013696:Temperature
chemical_list: D008051:Lipid Bilayers; C109237:OmpF protein; D018272:Porins