IUBMB Enzyme Nomenclature


Accepted name: phytoene desaturase (lycopene-forming)

Reaction: 15-cis-phytoene + 4 acceptor = all-trans-lycopene + 4 reduced acceptor (overall reaction)
(1a) 15-cis-phytoene + acceptor = all-trans-phytofluene + reduced acceptor
(1b) all-trans-phytofluene + acceptor = all-trans-ζ-carotene + reduced acceptor
(1c) all-trans-ζ-carotene + acceptor = all-trans-neurosporene + reduced acceptor
(1d) all-trans-neurosporene + acceptor = all-trans-lycopene + reduced acceptor

For diagram of reaction click here.

Other name(s): 4-step phytoene desaturase; four-step phytoene desaturase; phytoene desaturase (ambiguous); CrtI (ambiguous)

Systematic name: 15-cis-phytoene:acceptor oxidoreductase (lycopene-forming)

Comments: Requires FAD. The enzyme is involved in carotenoid biosynthesis and catalyses up to four desaturation steps (cf. EC [phytoene desaturase (neurosporene-forming)], EC [phytoene desaturase (ζ-carotene-forming)] and EC [phytoene desaturase (3,4-didehydrolycopene-forming)]).

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


1. Fraser, P.D., Misawa, N., Linden, H., Yamano, S., Kobayashi, K. and Sandmann, G. Expression in Escherichia coli, purification, and reactivation of the recombinant Erwinia uredovora phytoene desaturase. J. Biol. Chem. 267 (1992) 19891-19895. [PMID: 1400305]

[EC created 2011]

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