IUBMB Enzyme Nomenclature


Accepted name: lycopene ε-cyclase

Reaction: carotenoid ψ-end group = carotenoid ε-end group

For diagram of reaction click here and mechanism click here.

Other name(s): CrtL-e; LCYe; carotenoid ψ-end group lyase (decyclizing)

Systematic name: carotenoid ψ-end group lyase (ring-opening)

Comments: The carotenoid lycopene has the ψ-end group at both ends. When acting on one end, this enzyme forms δ-carotene. When acting on both ends, it forms ε-carotene.

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


1. Cunningham, F.X., Jr. and Gantt, E. One ring or two? Determination of ring number in carotenoids by lycopene ε-cyclases. Proc. Natl. Acad. Sci. USA 98 (2001) 2905-2910. [PMID: 11226339]

2. Stickforth, P., Steiger, S., Hess, W.R. and Sandmann, G. A novel type of lycopene ε-cyclase in the marine cyanobacterium Prochlorococcus marinus MED4. Arch. Microbiol. 179 (2003) 409-415. [PMID: 12712234]

[EC created 2011]

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