You've probably already noticed a firefly glowing in the night. It, like some fish, molluscs, fungi, dinoflagellates and mosquitoes, has an interesting characteristic: a bioluminescence. This characteristic concerns the ability of a living being to produce cold and visible light.
THE bioluminescence it is related to the defense and attraction of partners of many species. In fungi, some researchers believe that it is just a consequence of the process of obtaining food for these beings, others claim that it serves to attract insects that carry spores.
In general, light is generated thanks to an enzyme called luciferase, through an exothermic reaction. This enzyme is capable of oxidizing a substance called luciferin. In carrying out this process, energy that emits light is released. It is important to highlight that luciferin is the name of any substance capable of giving rise to bioluminescence, being distinct in the different types of organisms capable of emitting light.
Most bioluminescent living beings are marine. They emit light of varying colors, blue being the most common. In these animals, the function is usually related to protection against predators, and the animal can even camouflage itself or release substances that deceive the predator. Among the marine species that present bioluminescence, we can mention the lantern fish, a fish that inhabits deep waters.
Bioluminescence is currently used in medicine with the so-called green fluorescent protein (GFP), in addition to some luciferases that are used as markers. GFP is a protein taken from bioluminescent jellyfish that emits green fluorescence when irradiated with blue light. It is used to mark viruses and bacteria, for example, and observe them through the emitted fluorescence, thus tracking infections. It is also possible to label leukocytes during inflammatory processes. For the discovery of GFP and work developed in the field of medicine, researchers Osamu Shimomura, Martin Chalfie and Roger Tsien won the Nobel Prize in Chemistry in 2008.
In addition to the medical field, man has tried to use luciferins in various ways, including to improve public lighting. Some researchers have suggested creating bioluminescent trees, as they would emit light and, thus, spending on public lighting would be reduced.
By Ma. Vanessa dos Santos
Source: Brazil School - https://brasilescola.uol.com.br/o-que-e/biologia/o-que-e-bioluminescencia.htm
