Catalyses the two-electron reduction of biliverdin IXα at the C15 methine bridge. It has been proposed that this enzyme and EC 188.8.131.52, phycoerythrobilin:ferredoxin oxidoreductase, function as a dual enzyme complex in the conversion of biliverdin IXα into phycoerythrobilin.
Frankenberg, N., Mukougawa, K., Kohchi, T. and Lagarias, J.C. Functional genomic analysis of the HY2 family of ferredoxin-dependent bilin reductases from oxygenic photosynthetic organisms. Plant Cell13 (2001) 965–978. [PMID: 11283349]