Luciferase is a generic term for the class of oxidative enzymes that produce bioluminescence, and is distinct from a photoprotein. The name is derived from Lucifer, the root of which means 'light-bearer' (lucem ferre). One example is the firefly luciferase from the firefly Photinus pyralis. "Firefly luciferase" as a laboratory reagent often refers to P. pyralis luciferase although recombinant luciferases from several other species of fireflies are also commercially available.