Engineering of formate dehydrogenase for improving conversion potential of carbon dioxide to formate

Abstract

Abstract Formate dehydrogenase (FDH) is a D-2-hydroxy acid dehydrogenase, which can reversibly reduce CO2 to formate and thus act as non-photosynthetic CO2 reductase. In order to increase catalytic efficiency of formate dehydrogenase for CO2 reduction, the formate dehydrogenase CbFDHM2 was used as the parent to conduct single-site saturation and iterative combinatorial mutagenesis, and two mutants V328I/F285W and V354G/F285W were obtained of which reduction activity was about two times more than the CbFDHM2 and had greater potential in CO2 reduction. The optimal temperature for V328I/F285W and V354G/F285W was 55℃, and the optimal pH was 9.0. Then the molecular basis for its improvement of biochemical characteristics were preliminarily elucidated by computer-aided methods. All of these results further established a solid foundation for molecular modification of formate dehydrogenase and CO2 reduction.