Interaction of individual ions, ion-water clusters with aquaglyceroporin and aquaporin-1 channels

Abstract

Aquaglyceroporin and aquaporin-1 channels provide a mechanism for the transport of water and ions through cell membranes. The present paper proposes a precise geometric structure of these channels to explain their mechanism as selective channels. It provides a mathematical model to deduce the potential energy of the interaction between non-bonded individual molecules, such as calcium chloride and sodium chloride, interacting with aquaglyceroporin and aquaporin-1 channels, which are assumed to comprise two flaired right cylinders. We evaluate the potential energy both as arising from the calcium, sodium and chlorine as discrete atoms, interacting with the aquaglycero- porin and aquaporin-1 channels which are assumed to have atoms uniformly distributed throughout their volumes. Furthermore, we investigate the van der Waals interaction between ion-water cluster and aquaporins. We present numerical results describing the acceptance of individual molecules inside the aquaporin channels. Our calculations predict that calcium, sodium and chlorine ions and ion-water clusters are readily accepted into the aquaporins.