Crowded Charge in Biological Ion Channels

D.Gillespie, R.S. Eisenberg and W.Nonner
Univ. of Miami School of Medicine, US

Keywords: Ion Channels

Abstract:
Biological ion channels are devices very much like FETs, but conduct ions with chemical properties that are usually described by quantum mechanics (that is, delocalization of electrons between ion and channel protein). In the last twenty years physical chemists have shown that most of the thermodynamic properties of concentrated ionic solutions arise from the net charge and excluded volume of the ions and do not involve first-order quantum effects. The pores of ion channels usually are highly charged and so involve the crowding of charges and counterions in a nanoscale volume. The known properties of concentrated ionic solutions can be combined with some small, but critical, knowledge of channel structure to predict complex ionic specificities of channels. We present examples concerning calcium, sodium, chloride, cation, and potassium channels.

NSTI Nanotech 2003 Conference Technical Program Abstract