IUBMB Enzyme Nomenclature


Accepted name: lutein isomerase

Reaction: lutein = meso-zeaxanthin

For diagram of reaction click here.

Glossary: lutein = (3R,3'R)-dihydroxy-α-carotene
meso-zeaxanthin = (3R,3'S)-β,β-carotene-3,3'-diol

Other name(s): RPE65 (gene name); meso-zeaxanthin isomerase

Systematic name: lutein Δ45-isomerase

Comments: The enzyme is found in the retinal pigment epithelium (RPE) of vertebrates. It also has the activity of EC, retinoid isomerohydrolase.

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


1. Shyam, R., Gorusupudi, A., Nelson, K., Horvath, M.P. and Bernstein, P.S. RPE65 has an additional function as the lutein to meso-zeaxanthin isomerase in the vertebrate eye. Proc. Natl Acad. Sci. USA 114 (2017) 10882-10887. [PMID: 28874556]

[EC created 2018]

Return to EC 5.3.3 home page
Return to EC 5.3 home page
Return to EC 5 home page
Return to Enzymes home page
Return to IUBMB Biochemical Nomenclature home page