ABSTRACT
In biological systems electric fields are invariably associated with interfaces-or better, interphases*-and they play an important role in many biological processes. To illustrate this we have only to pick at random a few examples from the wealth of bio(electro)chemical information available. A range of important regulatory events in cells, such as the activation of particular enzymes, may be mediated by electrostatic interactions with membrane surfaces (1,2). Electrostatic interactions affect the binding, insertion, and folding of proteins into membranes (3,4) and the fusion of phospholipid bilayers (5,6). The generation and rapid transmission of nerve impulses are based on changes in ionic permeability of membranes resulting from changes in electric fields (7-9). Both the photosynthetic apparatus and the respiratory chain involve extensive membrane-bound enzyme systems in which charge separation across the membrane is coupled to the production of ATP (9-11).
