A structural phylogeny for understanding 2-oxoacid oxidoreductase function

2-Oxoacid:ferredoxin oxidoreductases (OFORs) are essential enzymes in microbial one-carbon metabolism. They use thiamine pyrophosphate to reversibly cleave carbon-carbon bonds, generating low potential (∼-500mV) electrons. Crystallographic analysis of a recently discovered OFOR, an oxalate oxidoreductase (OOR), has provided a second view of OFOR architecture and active site composition. Using these recent structural data along with the previously determined structures of pyruvate:ferredoxin oxidoreductase, structure-function relationships in this superfamily have been expanded and re-evaluated. Additionally, structural motifs have been defined that better serve to distinguish one OFOR subfamily from another and potentially uncover novel OFORs.