Workshop on Ion Channels, Fri, 12 Oct, 2007
Speaker: Dezso Boda
Abstract
We used a reduced model of calcium and sodium channels to study the selectivity mechanisms of these channels. Our model includes a small high density site (the selectivity filter) surrounded by a low dielectric protein. It is connected to a large low density bath with which it is in equilibrium. We treat ions and some protein side chains (characteristic of the given channel) explicitly by charged hard spheres. The solvent, the protein, and the membranes are modeled as dielectric continua. We show that the selectivity of these channels is governed by the competition of electrostatic attraction and entropic hard sphere repulsion. Techninal details about an efficient sampling of the phase space will be given. In a Monte Carlo simulation, the potential energy of the system has to be calculated in every simulation step. The presence of dielectric inhomogeneities requires a numerical method to solve Poission's equation in the system. Our Induced Charge Computation method will be presented. The effect of the polarization charges induced on the dielectric boundaries (the channel wall) will be discussed.
URL: www.ricam.oeaw.ac.at/specsem/ssqbm/participants/abstracts/index.php
This page was made with 100% valid HTML & CSS - Send comments to Webmaster
Today's date and time is 04/23/24 - 08:40 CEST and this file (/specsem/ssqbm/participants/abstracts/index.php) was last modified on 12/18/12 - 11:01 CEST