How Interactions Control Molecular Transport in Channels

The motion of molecules across channels and pores is critically important for understanding mechanisms of many cellular processes. Here we investigate the mechanism of interactions in the molecular transport through nanopores by analyzing exactly solvable discrete stochastic models. According to this approach the channel transport is viewed as a set of chemical transitions between discrete states. It is shown that the strength and spatial distribution of molecule/channel interactions can strongly modify the particle current. Our analysis indicates that the most optimal transport is achieved when the binding sites are near the entrance or exit of the pore depending on the sign of interaction potential. In addition, the role of intermolecular interactions during the channel transport is studied, and it is argued that an increase in the flux can be observed for some optimal interaction strength. The mechanisms of these phenomena are discussed.