Selectivity Rules for the Ion Transport in Narrow Channels through Biological Membranes from Geometrical and Dynamical Properties
The influence of geometrical and dynamical properties of narrow transmembrane channels is studied within two model approaches both analytically and numerically. The parameters for the models are chosen in close relation to the Gramicidin A channel. It is demonstrated that anomalous diffusion behaviour (in comparison with the diffusion in aqueous solution) of different cations can be related to differences in the activation entropy resulting from geometrical properties of the channel, and to dynamical effects which are strongly correlated to the softness of the vibration of the pore forming molecular groups.
KeywordsPolar Group Rate Theory Activation Entropy Jump Rate Migrate Particle
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