An artificial [Fe4S4]-containing metalloenzyme for the reduction of CO2 to hydrocarbons

Artificial metalloenzymes have emerged as a promising approach to expanding the catalytic repertoire of biocatalysis and synthetic biology. Thereby, catalytically competent synthetic cofactors are incorporated into host proteins, allowing the management of abiotic transformations by chemo-genetic means. Herein, we present the synthesis of an artificial Fischer-Tropschase (FTase hereafter), which is capable of reducing CO2 to hydrocarbons under mild aqueous conditions. Capitalizing on the biotin-streptavidin technology, we synthesized a biotinylated [Fe4S4] cofactor and embedded it in streptavidin via supramolecular anchoring. The cofactor-protein complex was chemo-genetically optimized for FTase activity, highlighting the effect of the second coordination on the catalytic performance. Alongside, a thorough literature research on the aqueous stability and redox chemistry of synthetic [Fe4S4] clusters is presented, and lastly, the synthesis of an artificial Fe-porphyrin-containing metalloenzyme.