Function
Phycocyanobilin:ferredoxin oxidoreductase (PcyA) is a member of the Fd-dependent bilin family. PcyA reduces vinyl groups of biliverdin IX-α to yield phycocyanobilin[1]. Phycocyanobilin is a pigment precursor of the light-harvesting antennae in red algae and cyanobacteria.
Structural highlights
The U-shaped porphyrin-like substrate of PcyA - biliverdin IX-α - binds between the central β sheets and the C terminal α helices[2].
3D Structures of Phycocyanobilin:ferredoxin oxidoreductase
3ajg, 3i95 – SyPcyA (mutant) + biliverdin IX – Synechocystis
3ajh – SyPcyA (mutant) + biliverdin XIII
3i94 - SyPcyA + biliverdin XIII
3f0l, 3fom, 3nb8, 3nb9 – SyPcyA (mutant)
3i8u – SyPcyA + biliverdin derivative
References
- ↑ Tu SL, Gunn A, Toney MD, Britt RD, Lagarias JC. Biliverdin reduction by cyanobacterial phycocyanobilin:ferredoxin oxidoreductase (PcyA) proceeds via linear tetrapyrrole radical intermediates. J Am Chem Soc. 2004 Jul 21;126(28):8682-93. PMID:15250720 doi:http://dx.doi.org/10.1021/ja049280z
- ↑ Wada K, Hagiwara Y, Yutani Y, Fukuyama K. One residue substitution in PcyA leads to unexpected changes in tetrapyrrole substrate binding. Biochem Biophys Res Commun. 2010 Nov 12;402(2):373-7. Epub 2010 Oct 12. PMID:20946883 doi:10.1016/j.bbrc.2010.10.037
