Nucleoside oxidase (H2O2 forming)

Nucleoside oxidase (H₂O₂-forming) (EC 1.1.3.39) is an enzyme with systematic name nucleoside:oxygen 5'-oxidoreductase (H₂O₂-forming). This enzyme catalyses the following chemical 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

This enzyme contains Heme and belongs to a flavoprotein family.