Involved in formate-dependent uric acid degradation under microaerobic and anaerobic conditions. May reduce the enzymes necessary for uric acid degradation. Binds 5 [4Fe-4S] clusters. Induced under anaerobic and microaerobic conditions (PubMed:8955321, PubMed:30885932). This control is mediated by Fnr, NarX, NarQ and NarL (PubMed:8955321). Expression is not reduced by the addition of respiratory electron acceptors, including nitrate, under anaerobic conditions (PubMed:30885932). Contains an N-terminal 4Fe-4S dicluster domain and a C-terminal pyridine nucleotide-disulfide oxidoreductase domain. Under aerobic and anaerobic conditions, the disruption mutant is able to grow utilizing ammonium, L-alanine, L-arginine, L-glutamic acid, glycine, or DL-serine as the sole nitrogen source.