ABSTRACT
One of the major functions of highly developed biomolecular superstructures in living systems is to shuttle electrons to sites where they are required to support life processes. Nature has learned how to do this very efficiently, often by designing supramolecular structures uniquely suited to the task. One example is the reaction center (RC) of the purple bacteria Rhodobacter sphaeroides, an integral membrane protein complex comprised of three protein subunits with multiple bound redox cofactors that are arranged to convert light into a transmembrane electrical potential [1-3]. This takes place via multiple electron transfers to drive photosynthesis and provide us with food and oxygen. Other examples include the membranebound liver cytochrome P450 (cyt P450) enzymes. One or more reductase enzymes bind to cyt P450s on membrane surfaces to deliver electrons from NAD(P)H for oxidative metabolism of lipophilic pollutans and drugs [4,5] These examples illustrate the integral use of membranes by living systems for organizing supramolecular structures [6] that are utilized in electron transfer events. Such systems can be used to guide the design of films for artificial devices aimed at biomedical sensing as well as bioreactors for catalytic chemical synthesis.
