Naphthalene 1,2-dioxygenase subunit alpha (NDO alpha subunit)

Naphthalene 1,2-dioxygenase subunit alpha is the large oxygenase component of the naphthalene dioxygenase (NDO) multicomponent enzyme system found in certain bacteria (notably *Pseudomonas* species). This subunit houses both a Rieske [2Fe-2S] iron–sulfur center, which accepts electrons from a ferredoxin, and a mononuclear nonheme iron active site responsible for catalysis. The enzyme initiates soil and water microbial degradation of polycyclic aromatic hydrocarbons (PAHs), including naphthalene, by catalyzing stereospecific cis-dihydroxylation of the aromatic ring. It is highly studied for its broad substrate range, regiospecificity, and use in bioremediation and biocatalysis. The alpha subunit operates within an \u03b1_3\u03b2_3 hexameric structure and interacts with smaller beta subunits. Despite structural and mechanistic characterization, it is not a classical or pharmacological drug target for human disease, and no drugs are clinically targeted to this enzyme.

Other names

NDO alpha subunitNaphthalene dioxygenase oxygenase component alpha subunitNaphthalene 1,2-dioxygenase large oxygenase component

Catalyzes the cis-dihydroxylation of aromatic rings by incorporating both atoms of molecular oxygen to form cis-dihydrodiols Functions via a Rieske [2Fe-2S] cluster and nonheme iron active site mechanism, with electron transfer from NAD(P)H via associated reductase and ferredoxin components