Nitroreductases are a family of evolutionarily related proteins

Protein family

A protein family is a group of evolutionarily-related proteins, and is often nearly synonymous with gene family. The term protein family should not be confused with family as it is used in taxonomy....

 involved in the reduction nitrogen containing compounds including those containing the nitro

Nitro compound

Nitro compounds are organic compounds that contain one or more nitro functional groups . They are often highly explosive, especially when the compound contains more than one nitro group and is impure. The nitro group is one of the most common explosophores used globally...

 functional group. Members of this family utilise FMN

FMN

FMN may refer to several things:* Flavin mononucleotide.* Forsvarsministeriet, the Danish Ministry of Defence.* Four Corners Regional Airport outside Farmington, New Mexico, its IATA airport code.* Fluid Music....

 as a cofactor

Cofactor (biochemistry)

A cofactor is a non-protein chemical compound that is bound to a protein and is required for the protein's biological activity. These proteins are commonly enzymes, and cofactors can be considered "helper molecules" that assist in biochemical transformations....

 and are often found to be homodimers.

Members of this family include oxygen-insensitive NAD(P)H nitroreductase (FMN-dependent nitroreductase) (6,7-dihydropteridine reductase

6,7-dihydropteridine reductase

In enzymology, a 6,7-dihydropteridine reductase is an enzyme that catalyzes the chemical reactionThe 3 substrates of this enzyme are 5,6,7,8-tetrahydropteridine, NAD+, and NADP+, whereas its 4 products are 6,7-dihydropteridine, NADH, NADPH, and H+....

) and NADH dehydrogenase

NADH dehydrogenase

NADH dehydrogenase is an enzyme located in the inner mitochondrial membrane that catalyzes the transfer of electrons from NADH to coenzyme Q...

 . A number of these proteins are described as oxidoreductases. They are primarily found in bacterial lineages though a number of eukaryotic homologs have been identified: C. elegans

Caenorhabditis elegans

Caenorhabditis elegans is a free-living, transparent nematode , about 1 mm in length, which lives in temperate soil environments. Research into the molecular and developmental biology of C. elegans was begun in 1974 by Sydney Brenner and it has since been used extensively as a model...

, D. melanogaster

Drosophila melanogaster

Drosophila melanogaster is a species of Diptera, or the order of flies, in the family Drosophilidae. The species is known generally as the common fruit fly or vinegar fly. Starting from Charles W...

, , mouse and human . This protein is not found in photosynthetic eukaryotes. The sequences containing this entry in photosynthetic organisms are possible false positives.