title: Transportation behavior of alkali ions through a cell membrane ion channel. A quantum chemical description of a simplified isolated model.
abstract: Quantum chemical model calculations were carried out for modeling the ion transport through an isolated ion channel of a cell membrane. An isolated part of a natural ion channel was modeled. The model channel was a calixarene derivative, hydrated sodium and potassium ions were the models of the transported ion. The electrostatic potential of the channel and the energy of the channel-ion system were calculated as a function of the alkali ion position. Both attractive and repulsive ion-channel interactions were found. The calculations - namely the dependence of the system energy and the atomic charges of the water molecules with respect to the position of the alkali ion in the channel - revealed the molecular-structural background of the potassium selectivity of this artificial ion channel. It was concluded that the studied ion channel mimics real biological ion channel quite well.
authors.affiliation: Department of Physical Chemistry, Budapest University of Technology and Economics, H-1521, Budapest, Budafoki út 8., Hungary. fbilles@mail.bme.hu
authors.forename: Ferenc
authors.initials: F
authors.lastname: Billes
authors.forename: Ildikó
authors.initials: I
authors.lastname: Mohammed-Ziegler
authors.forename: Hans
authors.initials: H
authors.lastname: Mikosch
mesh_terms: D000468:Alkalies; D047250:Calixarenes / Q000737:chemistry*; D002462:Cell Membrane; D003198:Computer Simulation; D006860:Hydrogen Bonding; D008958:Models, Molecular; D008968:Molecular Conformation; D011188:Potassium / Q000737:chemistry; D061216:Potassium Ionophores / Q000737:chemistry*; D011789:Quantum Theory; D012964:Sodium / Q000737:chemistry; D013055:Spectrophotometry, Infrared; D013816:Thermodynamics
chemical_list: D000468:Alkalies; D061216:Potassium Ionophores; D047250:Calixarenes; D012964:Sodium; D011188:Potassium