Reaction: nitric oxide + H2O + ferricytochrome c = nitrite + ferrocytochrome c + 2 H+
Glossary: nitric oxide = NO = nitrogen(II) oxide
Other name(s): cd-cytochrome nitrite reductase; [nitrite reductase (cytochrome)] [misleading, see comments.]; cytochrome c-551:O2, NO2+ oxidoreductase; cytochrome cd; cytochrome cd1; hydroxylamine (acceptor) reductase; methyl viologen-nitrite reductase; nitrite reductase (cytochrome; NO-forming)
Systematic name: nitric-oxide:ferricytochrome-c oxidoreductase
Comments: The reaction is catalysed by two types of enzymes, found in the perimplasm of denitrifying bacteria. One type comprises proteins containing multiple copper centres, the other a heme protein, cytochrome cd1. Acceptors include c-type cytochromes such as cytochrome c-550 or cytochrome c-551 from Paracoccus denitrificans or Pseudomonas aeruginosa, and small blue copper proteins such as azurin and pseudoazurin. Cytochrome cd1 also has oxidase and hydroxylamine reductase activities. May also catalyse the reaction of hydroxylamine reductase (EC 18.104.22.168) since this is a well-known activity of cytochrome cd1.
Links to other databases: BRENDA, EAWAG-BBD, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 9080-03-9
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