Theoretical simulation of ionic transport through a transmembrane channel.

The two-site model of Urry for the ionic conduction through a gramicidin A channel has been confirmed by theoretical calculations, using a method developed at this laboratory, which yields the potential energy profile of the ion along the channel. Preliminary results show that the pore closure could start with the spatial rearrangement of the--HN--CH3 terminal chain under the influence of the ion already in the channel.