Carotenoid Oxygenase


Family Ties


            The retinol-forming carotenoid oxygenases form a sequence-related family consisting of over 100 members.  These enzymes differ in their substrates and their method of cleavage.  Some examples of carotenoid oxygenases are:



What InterPro Tells Us:


Q9HAY6 Human beta‑carotene‑15,15’‑monooxygenase


InterPro Domain Architecture:


InterPro Entry

Method Accession

Graphical Match

Method Name








From the graphical match above, you can see that the signatures (method accession) represent one InterPro entry for human beta‑carotene‑15,15’‑monooxygenase, namely IPR004294, which represents the family of carotenoid oxygenases as characterised by the retinal pigment epithelial membrane protein RPE65.  This entry has two signatures, PF03055 from the PFAM database, and PTHR10543 from the PANTHER database, where both signatures cover the entire protein length.  The InterPro entry gives details regarding the taxonomic distribution of carotenoid oxygenases.


What the Structure Tells Us


            The structure of the apocaretnoid‑15,15’‑oxygenase (lignostilbene-alpha,beta-dioxygenase) from the cyanobacteria Synechocystis sp. has been determined, and can be used as a template to explore the structures of other carotenoid oxygenases.  This structure can be found in the Protein Data Bank (PDB).  A detailed description and visualisation of the structural features of carotenoid oxygenases can be found at the PDB ‘Molecule of the Month’, providing insights into how these molecules cleave carotenoids.


Next:  Table of Carotenoid Oxygenases

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