Widening the Product Profile of Carbon Dioxide Reduction by Vanadium Nitrogenase

摘要

Two V-nitrogenase-based reaction systems were previously shown to reduce CO2 to hydrocarbons: (1) an enzyme-based system, which requires both components of V-nitrogenase for ATP-dependent reduction of CO2 to ≤C2 hydrocarbons; and (2) a cofactor-based system, which employs SmI2 to supply electrons to the isolated V-cluster for ATP-independent reduction of CO2 to ≤C3 hydrocarbons. Here, we report ATP-independent reduction of CO2 to hydrocarbons by a reaction system comprising Eu(II) DTPA and VFe protein. Combining features of both enzyme- and cofactor-based systems, this system demonstrates an improved activity of C-C coupling, as well as a widened product profile of ≤C4 hydrocarbons. The C-C coupling does not route via CO2-derived CO, and it is significantly enhanced in D2O. These observations afford the initial insights into the characteristics of this unique reaction and provide a potential template for future design of catalysts to recycle the greenhouse gas CO2 into useful products.