IUBMB Enzyme Nomenclature


Accepted name: NAD(P)H oxidase (H2O-forming)

Reaction: 2 NAD(P)H + 2 H+ + O2 = 2 NAD(P)+ + 2 H2O

Systematic name: NAD(P)H:oxygen oxidoreductase (H2O-forming)

Comments: A flavoprotein (FAD). NADPH is a better substrate than NADH [1,3]. By removal of oxygen the enzyme is involved in aerobic tolerance in the thermophilic anaerobic archaeon Thermococcus profundus and in Giardia intestinalis, a microaerophilic single-celled parasite of the order Diplomonadida.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:


1. Brown, D.M., Upcroft, J.A. and Upcroft, P. A H2O-producing NADH oxidase from the protozoan parasite Giardia duodenalis. Eur. J. Biochem. 241 (1996) 155-161. [PMID: 8898901]

2. Li, L. and Wang, C.C. A likely molecular basis of the susceptibility of Giardia lamblia towards oxygen. Mol. Microbiol. 59 (2006) 202-211. [PMID: 16359329]

3. Jia, B., Park, S.C., Lee, S., Pham, B.P., Yu, R., Le, T.L., Han, S.W., Yang, J.K., Choi, M.S., Baumeister, W. and Cheong, G.W. Hexameric ring structure of a thermophilic archaeon NADH oxidase that produces predominantly H2O. FEBS J. 275 (2008) 5355-5366. [PMID: 18959761]

4. Jia, B., Lee, S., Pham, B.P., Cho, Y.S., Yang, J.K., Byeon, H.S., Kim, J.C. and Cheong, G.W. An archaeal NADH oxidase causes damage to both proteins and nucleic acids under oxidative stress. Mol. Cells 29 (2010) 363-371. [PMID: 20213313]

[EC created 2013]

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