Bioluminescence in Dinoflagellates
Bioluminescence can be defined as the production of visible light by living organisms. Around 18 species of dinoflagellates are bioluminescent, and most of them emit blue-green light. These species contain scintillons, individual cytoplasmic bodies present in the cell vacuole. They contain dinoflagellate luciferase, the enzyme involved in dinoflagellate bioluminescence, and luciferin, a chlorophyll-derived tetrapyrrole ring that acts as the substrate to the light-producing reaction. The reaction is sensitive to the pH. When the pH drops, luciferase changes its shape, allowing luciferin to bind. When mechanically stimulated—by boat, swimming, or waves, a blue flash of light occur as luminescence on the ocean surface at night. Dinoflagellates use bioluminescence as a defense mechanism. They scare their predators by flashing lights. Examples of bioluminescence-producing species are Gonyaulax, Alexandrium, and Ceratium.
Dinoflagellates
Dinoflagellates are single-celled eukaryotes that belong to the kingdom Protista. They are considered to be among the most primitive eukaryotes. These organisms are mostly marine and photosynthetic in nature. They have characteristics of both plants and animals. Dinoflagellates are also responsible for phenomena such as red tides and bioluminescence on the ocean surface.