Monolayers of Membrane Proteins

Abstract

In biological membranes, among many different transport phenomena, ion transport is one of the major processes that are vital for all kinds of cell function. The extensive studies over the past few decades of the mechanisms of ion transport across artificial membranes have revealed a great deal both about ionophores themselves and about the properties lipid membranes must have for the ionophores to function efficiently. In the case of a carrier molecule, for example, it is of little value for it to have a high ion selectivity if it does not combine with the membrane or, if it does combine, if it does not move or bind ions in the membrane. In the case of pore-forming molecules, binding to different membranes may be very similar, but the efficiency of the transport process may depend critically on the state of ionization of the lipid or on the membrane thickness.