DIRECT ELECTRON-TRANSFER TO ESCHERICHIA-COLI FUMARATE REDUCTASE IN SELF-ASSEMBLED ALKANETHIOL MONOLAYERS ON GOLD ELECTRODES

A strong cathodic current response to the presence of fumarate provides evidence of direct electron transfer to membrane-bound E. coli fumarate reductase in membrane-mimetic alkanethiol monolayers on gold electrodes. This electroenzymatic response is attenuated reversibly by the competitive enzyme inhibitor, oxaloacetate. The hydrophobic enzyme is coadsorbed with alkanethiols on gold in a novel detergent dialysis process. This approach could lead to novel sensors and biocatalytic devices and may provide an ideal means to study the electron transfer characteristics of membrane-bound redox proteins in a readily manipulable membrane-mimetic medium.