Nitroreductase (NR)

The nitroreductase family is comprised of a group of FMN- or FAD-dependent enzymes that are able to metabolize nitrosubstituted compounds using the reducing power of NAD(P)H. These nitroreductases can be found in bacterial species and, to a lesser extent, in eukaryotes.There is little information on the biochemical functions of nitroreductases. Some studies suggest their possible involvement in the oxidative stress response. In the yeast Saccharomyces cerevisiae, two nitroreductase proteins, Frm2p and Hbn1p, have been described. While Frm2p appears to act in the lipid signalling pathway, the function of Hbn1p is completely unknown. These strains exhibited less ROS accumulation and lipid peroxidation when exposed to peroxides, H(2)O(2) and t-BOOH.