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 provide s evidence of direct electron transfer to membrane-bound E. coli fumar ate reductase in membrane-mimetic alkanethiol monolayers on gold elect rodes. 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 pro cess. This approach could lead to novel sensors and biocatalytic devic es and may provide an ideal means to study the electron transfer chara cteristics of membrane-bound redox proteins in a readily manipulable m embrane-mimetic medium.