Construction of a biocathode using the multicopper oxidase from the hyperthermophilic archaeon, Pyrobaculum aerophilum: towards a long-life biobattery.

Objectives: The life of biobatteries remains an issue due to loss of enzyme activity over time. In this study, we sought to develop a biobattery with a long life using a hyperthermophilic enzyme.

Results: We hypothesized that use of such hyperthermophilic enzymes would allow for the biofuel cells to have a long battery life. Using pyrroloquinoline quinone-glucose dehydrogenase and the multicopper oxidase from Pyrobaculum aerophilum, we constructed an anode and cathode. The maximum output was 11 μW at 0.2 V, and the stability of the both electrode was maintained at 70 % after 14 days.

Conclusion: The biofuel cells that use hyperthermophilic enzymes may prolong their life.