Kinetics of Mediated Bioelectrocatalytic Oxidation of Glucose by Protein Extracts of Escherichia coli

The kinetics of bioelectrocatalytic oxidation of glucose by protein extracts—supersonic-destruction products of Escherichia coli BB cells—is studied in the presence of [Fe(CN) 6 ] 3– as the mediator system. The effect of the concentration of mediator, glucose, and protein extract is studied by electrochemical methods. The results are used in determination of effective parameters: the rate constant of glucose biooxidation, the constant of substrate-induced inhibition, and the activation energy. It is shown that the activation energy of this reaction falls into the interval of activation energies of dehydrogenase reactions. The voltammetric characteristics of a model asymmetrical biofuel cell which employs the protein extract as the anodic catalyst are determined. The maximum specific power of such model biofuel cell is found to be 400 µW/cm 2 (4 W/m 2 ).