Phycocyanobilin:ferredoxin oxidoreductase

In enzymology, a phycocyanobilin:ferredoxin oxidoreductase (PcyA, ) is an enzyme that catalyzes the chemical reaction


 * (3Z)-phycocyanobilin + oxidized ferredoxin $$\rightleftharpoons$$ biliverdin IXalpha + reduced ferredoxin

Thus, the two substrates of this enzyme are (3Z)-phycocyanobilin and oxidized ferredoxin, whereas its two products are biliverdin IXalpha and reduced ferredoxin.

This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-CH group of donor with an iron-sulfur protein as acceptor. The systematic name of this enzyme class is (3Z)-phycocyanobilin:ferredoxin oxidoreductase. This enzyme participates in porphyrin and chlorophyll metabolism.

Structural studies
As of late 2007, 3 structures have been solved for this class of enzymes, with PDB accession codes, , and.