Dictionary of Ichthyology  

luciferin = a substance concerned in bioluminescence, being oxidized in the presence of the enzyme luciferase to produce oxyluciferin and light.

Luciferin model and a luciferin-luciferase reaction from Wikimedia Commons: http://commons.wikimedia.org/wiki/File:Luciferin.png and http://commons.wikimedia.org/wiki/File:Luciferin_principle.png

Canadian Museum of Nature
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