Dissimilatory Nitrate Reductase

Abstract

The dissimilatory nitrate reductase (NAP) from Desulfovibrio desulfuricans ATCC 27774 catalyses the reduction of nitrate to nitrite for respiration. It belongs to the DMSO reductase family of molybdoenzymes and contains one single subunit of 755 amino acids with one molybdenum cofactor and one [4Fe–4S] cluster. The Mo atom is coordinated by two cis ‐dithiolene groups of two molybdopterin guanine dinucleotides (MGD), by the sulfur atom of Cys140 and by one OH/OH 2 ligand. One of the MGD cofactors is directly involved in the electron transfer between the molybdenum center and the [4Fe–4S] cluster.