IUBMB Enzyme Nomenclature


Accepted name: nucleoside oxidase (H2O2-forming)

Reaction: adenosine + 2 O2 + H2O = 9-riburonosyladenine + 2 H2O2 (overall reaction)
(1a) adenosine + O2 = 5'-dehydroadenosine + H2O2
(1b) 5'-dehydroadenosine + O2 + H2O = 9-riburonosyladenine + H2O2

Systematic name: nucleoside:oxygen 5'-oxidoreductase (H2O2-forming)

Comments: A heme-containing flavoprotein (FAD). Other purine and pyrimidine nucleosides (as well as 2'-deoxyribonucleosides and arabinosides) are substrates, but ribose and nucleotides are not substrates. The overall reaction takes place in two separate steps steps, with the 5'-dehydro nucleoside being released from the enzyme to serve as substrate for the second reaction. This enzyme differs from EC, nucleoside oxidase, as it produces hydrogen peroxide rather than water. Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:


1. Koga, S., Ogawa, J., Cheng, L.Y., Choi, Y.M., Yamada, H. and Shimizu, S. Nucleoside oxidase, a hydrogen peroxide-forming oxidase, from Flavobacterium meningosepticum. Appl. Environ. Microbiol. 63 (1997) 4282-4286.

[EC created 2001]

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