Larger organisms, such as a jellyfish, can luminesce for tens of seconds. In most multi-cellular organisms, the ability to produce light is controlled neurally. However, the transmitter that signals the change to take place is unknown in most organisms. Luminescence can also be induced by the presence of another luminescing organism. A few characteristics are common to all bioluminescent reactions.
All bioluminescent reactions occur in the presence of oxygen.
The luciferin is the basic substrate of the reaction and produces the light. The luciferase catalyzes the reaction. In the basic reaction, the luciferase catalyzes the oxidation of luciferin, which results in two products- light and inactive oxyluciferin. In most organisms, new luciferin must be brought to the system either by diet or internal synthesis for each reaction. Sometimes the luciferin and luciferase are bound together in one unit called a photoprotein.