Mechanisms of CO2 reduction in bacteria based on molecular studies of formate dehydrogenase (FDH) enzymes

Abstract

Formate dehydrogenase (FDHs) is an enzyme that catalyzes the oxidation of formate (HCOO–) to carbon dioxide (CO2) and water, with the concomitant reduction of a cofactor such as NAD+ (nicotinamide adenine dinucleotide) or NADP+ (flavin adenine dinucleotide). This process produces energy, which cells can then employ for various metabolic functions. FDHs are key metabolic enzymes that perform critical roles in energy production, carbon dioxide fixation, and nitrogen metabolism in many bacterial species. FDH is a D-specific 2-hydroxy acid dehydrogenase found mostly in prokaryotes and eukaryotes. It is essential for the energy supply of methyl tropic organisms through hydride ion transfer and bio-transformations. Most metal-binding FDH enzymes, such as molybdenum and tungsten-containing enzymes, catalyze the redox process and oxidation of formate and serve as flexible biocatalysts for NADPH regeneration and consumption. Formate dehydrogenase is also utilized in biotechnology and biochemistry as a technique. It is extensively employed as an electron acceptor in enzymatic tests to create hydrogen gas via proton reduction. Furthermore, formate dehydrogenase has been researched for its potential application in the production of biofuels and other bioproducts. The current reviews emphasize the structural and functional characteristics of FDH and the primary mechanisms involved in FDH development. It examines the function of metal ions in FDH as well as its catalytic mechanism and characteristics.