catalytic domain of flavodiiron proteins (FDPs) and related proteins; MBL-fold metallo-hydrolase domain
FDPs catalyze the reduction of oxygen and/or nitric oxide to water or nitrous oxide respectively. In addition to this N-terminal catalytic domain they contain a C-terminal flavin mononucleotide-binding flavodoxin-like domain. Although some FDPs are able to reduce NO or O2 with similar catalytic efficiencies others are selective for either NO or O2, such as Escherichia coli flavorubredoxin which is selective toward NO and G. intestinalis FDP which is selective toward O2. These enzymes belong to the MBL-fold metallo-hydrolase superfamily which is comprised mainly of hydrolytic enzymes which carry out a variety of biological functions. Some members of this subgroup are single domain.
Jiyao W et al.(2023). "The conserved domain database in 2023.",