Multiple electron transfer pathways of tungsten-containing formate dehydrogenase in direct electron transfer-type bioelectrocatalysis.

Tungsten-containing formate dehydrogenase from AM1 (FoDH1)-a promising biocatalyst for the interconversion of carbon dioxide/formate and nicotine adenine dinucleotide (NAD)/NADH redox couples-was investigated using structural biology and bioelectrochemistry. FoDH1 is reported to be an enzyme that can realize "direct electron transfer (DET)-type bioelectrocatalysis." However, its 3-D structure, electrode-active sites, and electron transfer (ET) pathways remain unclear.