IUBMB Enzyme Nomenclature


Accepted name: C-phycoerythrin α-cysteine-82 phycoerythrobilin lyase

Reaction: a [C-phycoerythrin α-subunit]-Cys82-phycoerythrobilin = apo-[C-phycoerythrin α-subunit] + (3E)-phycoerythrobilin

Other name(s): cpeY (gene name)

Systematic name: [C-phycoerythrin α-subunit]-Cys82-phycoerythrobilin:phycoerythrobilin lyase

Comments: The enzyme, characterized from the cyanobacterium Microchaete diplosiphon, catalyses the attachment of the phycobilin chromophore (3E)-phycoerythrobilin (PEB) to cysteine 82 of the α subunit of the phycobiliprotein C-phycoerythrin. The numbering used here corresponds to the enzyme from Microchaete diplosiphon, and could vary slightly in other organisms. Activity is greatly enhanced in the presence of the chaperone-like protein CpeZ. The reaction could also be catalysed by EC, phycobiliprotein cysteine-84 phycobilin lyase, but much less efficiently.

Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:


1. Biswas, A., Boutaghou, M.N., Alvey, R.M., Kronfel, C.M., Cole, R.B., Bryant, D.A. and Schluchter, W.M. Characterization of the activities of the CpeY, CpeZ, and CpeS bilin lyases in phycoerythrin biosynthesis in Fremyella diplosiphon strain UTEX 481. J. Biol. Chem. 286 (2011) 35509-35521. [PMID: 21865169]

2. Kronfel, C.M., Biswas, A., Frick, J.P., Gutu, A., Blensdorf, T., Karty, J.A., Kehoe, D.M. and Schluchter, W.M. The roles of the chaperone-like protein CpeZ and the phycoerythrobilin lyase CpeY in phycoerythrin biogenesis. Biochim Biophys Acta Bioenerg 1860 (2019) S0005-2728(. [PMID: 31173730]

[EC created 2021]

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