Direct detection of a single [4Fe‐4S] cluster in a tungsten‐containing enzyme: Electrochemical conversion of CO ₂ into formate by formate dehydrogenase

The conversion of CO2 into fuels and valuable chemicals is one the central topics to combat climate change meet growing demand for renewable energy. Herein, we show that formate dehydrogenase from Clostridium ljungdahlii (ClFDH) adsorbed on electrodes displays clear characteristic voltammetric signals can be assigned reduction oxidation potential [4Fe-4S]2+/+ cluster under nonturnover conditions. Upon adding substrates, transform a specific redox center engages in catalytic electron transport. ClFDH catalyzes rapid efficient reversible interconversion between presence substrates. turnover frequency electrochemical determined as 1210 s−1 at 25 °C pH 7.0, which further enhanced up 1786 50°C. Faradaic efficiency −0.6 V (vs. standard hydrogen electrode) recorded 99.3% 2-h reaction. Inhibition experiments theoretical modeling disclose interesting pathways entry, exit, OCN− competition, suggesting an oxidation-state-dependent binding mechanism catalysis. Our results provide different perspective understanding FDH original insights design synthetic catalysts.