Cypridina-luciferin 2-monooxygenase () is an enzyme that catalyzes the chemical reaction
Thus, the two substrates of this enzyme are vargulin and oxygen. Its products are oxidized vargulin, carbon dioxide, and a photon.
This enzyme belongs to the family of oxidoreductases, specifically those acting on single donors with O<sub>2</sub> as oxidant and incorporation of two atoms of oxygen into the substrate (oxygenases). The oxygen incorporated need not be derived from O with incorporation of one atom of oxygen (internal monooxygenases o internal mixed-function oxidases). The systematic name of this enzyme class is Cypridina-luciferin:oxygen 2-oxidoreductase (decarboxylating). Other names in common use include Cypridina-type luciferase, luciferase (Cypridina luciferin), and Cypridina luciferase.
The primary sequence was determined by cloning the cDNA.