Enzymes from hyperthermophilic archaea are potential candidates for industrial use because of their superior pH, thermal, and long-term stability, and are expected to improve the long-term stability of biofuel cells (BFCs). However, the reported multicopper oxidase (MCO) from hyperthermophilic archaea has lower redox potential than MCOs from other organisms, which leads to a decrease in the cell voltage of BFCs. In this study, we attempted to positively shift the redox potential of the MCO from hyperthermophilic archaeon Pyrobaculum aerophilum (McoP). Mutations (M470L and M470F) were introduced into the axial ligand of the T1 copper atom of McoP, and the enzymatic chemistry and redox potentials were compared with that of the parent (M470). The redox potentials of M470L and M470F shifted positively by about 0.07 V compared with that of M470. In addition, the catalytic activity of the mutants towards 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) increased 1.2–1.3-fold. The thermal stability of the mutants and the electrocatalytic performance for O₂ reduction of M470F was slightly reduced compared with that of M470. This research provides useful enzymes for application as biocathode catalysts for high-voltage BFCs.

来自超嗜热古细菌的酶具有优异的pH值，热稳定性和长期稳定性，因此可能成为工业用途的酶，并且有望改善生物燃料电池（BFC）的长期稳定性。然而，据报道来自嗜热古细菌的多铜氧化酶（MCO）的氧化还原电位低于其他生物体的MCO，这导致BFC的细胞电压降低。在这项研究中，我们试图从超嗜热古生嗜热菌中积极改变MCO的氧化还原电位。（McoP）。将突变（M470L和M470F）引入McoP的T1铜原子的轴向配体中，并将​​其酶化学和氧化还原电势与亲本（M470）进行比较。与M470相比，M470L和M470F的氧化还原电位正向偏移约0.07V。此外，突变体对2,2'-叠氮基双（3-乙基苯并噻唑啉-6-磺酸）（ABTS）的催化活性增加了1.2-1.3倍。与M470相比，M470F的突变体的热稳定性和O ₂还原的电催化性能略有降低。这项研究提供了有用的酶，可用作高压BFC的生物阴极催化剂。