CcNiR
From Proteopedia
Your Heading Here (maybe something like 'ccNiR')
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Cytochrome c nitrite reductase is a multicenter enzyme that uses a five-coordinated heme to perform the reduction of nitrite to ammonium in a six-electron transfer reaction. In the sulfate reducing bacterium Desulfovibrio desulfuricans ATCC 27774, the enzyme is purified as a NrfA2NrfH complex that houses 14 hemes.
The catalytic reaction occurs at a high-spin (5-coordinated) heme that is located at a pentahemic subunit of 61 kDa which is strongly bound to its physiological electron donor, a smaller hydrophobic polypeptide tetrahemic of 19 kDa, composed of 4 c-types hemes; in vitro, the protein complexes associate each other forming huge aggregates (min. 890 kDa).
