Luciferin (from the Latin ''lucifer'', "light-bearer") is a generic term for the light-emitting

compound Compound may refer to: Architecture and built environments * Compound (enclosure), a cluster of buildings having a shared purpose, usually inside a fence or wall ** Compound (fortification), a version of the above fortified with defensive struc ...

found in organisms that generate bioluminescence. Luciferins typically undergo an

enzyme Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products ...

-catalyzed reaction with molecular oxygen. The resulting transformation, which usually involves splitting off a molecular fragment, produces an excited state intermediate that emits light upon decaying to its ground state. The term may refer to molecules that are substrates for both luciferases and

photoprotein Photoproteins are a type of enzyme, made of protein, from bioluminescent organisms. They add to the function of the luciferins whose usual light-producing reaction is catalyzed by the enzyme luciferase. History The term photoprotein was first use ...

Types

Luciferins are a class of small-molecule substrates that react with oxygen in the presence of a luciferase (an enzyme) to release

energy In physics, energy (from Ancient Greek: ἐνέργεια, ''enérgeia'', “activity”) is the quantitative property that is transferred to a body or to a physical system, recognizable in the performance of work and in the form of hea ...

in the form of

light Light or visible light is electromagnetic radiation that can be perceived by the human eye. Visible light is usually defined as having wavelengths in the range of 400–700 nanometres (nm), corresponding to frequencies of 750–420 te ...

. It is not known just how many types of luciferins there are, but some of the better-studied compounds are listed below. Because of the chemical diversity of luciferins, there is no clear unifying mechanism of action, except that all require molecular oxygen, The variety of luciferins and luciferases, their diverse reaction mechanisms and the scattered phylogenetic distribution indicate that many of them have arisen independently in the course of evolution.

Firefly

Firefly luciferin Firefly luciferin (also known as beetle luciferin) is the luciferin, or light-emitting compound, used for the firefly (Lampyridae), railroad worm ( Phengodidae), starworm ( Rhagophthalmidae), and click-beetle (Pyrophorini) bioluminescent systems. ...

is the luciferin found in many

Lampyridae The Lampyridae are a family of elateroid beetles with more than 2,000 described species, many of which are light-emitting. They are soft-bodied beetles commonly called fireflies, lightning bugs, or glowworms for their conspicuous production ...

species. It is the substrate of beetle luciferases ( EC 1.13.12.7) responsible for the characteristic yellow light emission from fireflies, though can cross-react to produce light with related enzymes from non-luminous species. The chemistry is unusual, as

adenosine triphosphate Adenosine triphosphate (ATP) is an organic compound that provides energy to drive many processes in living cells, such as muscle contraction, nerve impulse propagation, condensate dissolution, and chemical synthesis. Found in all known forms o ...

(ATP) is required for light emission, in addition to molecular

oxygen Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as ...

Snail

Latia luciferin is, in terms of chemistry, (''E'')-2-methyl-4-(2,6,6-trimethyl-1-cyclohex-1-yl)-1-buten-1-ol formate and is from the freshwater snail ''

Latia neritoides ''Latia neritoides'' is a species of small freshwater snail or limpet, an aquatic gastropod mollusc in the family Latiidae. The type specimen is in the British Museum. The specific epithet "neritoides" means "like a nerite". The shell of ...

''.EC 1.14.99.21
ORENZA: a database of ORphan ENZyme Activities, accessed 27 November 2009.

Bacterial

Bacterial luciferin is two-component system consisting of

flavin mononucleotide Flavin mononucleotide (FMN), or riboflavin-5′-phosphate, is a biomolecule produced from riboflavin (vitamin B2) by the enzyme riboflavin kinase and functions as the prosthetic group of various oxidoreductases, including NADH dehydrogenase, as we ...

and a fatty aldehyde found in

bioluminescent bacteria Bioluminescent bacteria are light-producing bacteria that are predominantly present in sea water, marine sediments, the surface of decomposing fish and in the gut of marine animals. While not as common, bacterial bioluminescence is also found in ...

Coelenterazine

Coelenterazine Coelenterazine is a luciferin, a molecule that emits light after reaction with oxygen, found in many aquatic organisms across eight phyla. It is the substrate of many luciferases such as '' Renilla reniformis'' luciferase (Rluc), ''Gaussia'' lucif ...

is found in

radiolarian The Radiolaria, also called Radiozoa, are protozoa of diameter 0.1–0.2 mm that produce intricate mineral skeletons, typically with a central capsule dividing the cell into the inner and outer portions of endoplasm and ectoplasm. The elab ...

s, ctenophores, cnidarians, squid,

brittle star Brittle stars, serpent stars, or ophiuroids (; ; referring to the serpent-like arms of the brittle star) are echinoderms in the class Ophiuroidea, closely related to starfish. They crawl across the sea floor using their flexible arms for locomot ...

s, copepods,

chaetognath The Chaetognatha or chaetognaths (meaning ''bristle-jaws'') are a phylum of predatory marine worms that are a major component of plankton worldwide. Commonly known as arrow worms, about 20% of the known Chaetognatha species are benthic zone, be ...

s, fish, and shrimp. It is the prosthetic group in the protein

aequorin Aequorin is a calcium-activated photoprotein isolated from the hydrozoan ''Aequorea victoria''. Its bioluminescence was studied decades before the protein was isolated from the animal by Osamu Shimomura in 1962. In the animal, the protein occur ...

responsible for the blue light emission.

Dinoflagellate

Dinoflagellate luciferin is a chlorophyll derivative (i. e. a

tetrapyrrole Tetrapyrroles are a class of chemical compounds that contain four pyrrole or pyrrole-like rings. The pyrrole/pyrrole derivatives are linked by ( =- or -- units), in either a linear or a cyclic fashion. Pyrroles are a five-atom ring with four car ...

) and is found in some dinoflagellates, which are often responsible for the phenomenon of nighttime glowing waves (historically this was called

phosphorescence Phosphorescence is a type of photoluminescence related to fluorescence. When exposed to light (radiation) of a shorter wavelength, a phosphorescent substance will glow, absorbing the light and reemitting it at a longer wavelength. Unlike fluo ...

, but is a misleading term). A very similar type of luciferin is found in some types of euphausiid shrimp.

Vargulin

Vargulin is found in certain

ostracod Ostracods, or ostracodes, are a class of the Crustacea (class Ostracoda), sometimes known as seed shrimp. Some 70,000 species (only 13,000 of which are extant) have been identified, grouped into several orders. They are small crustaceans, typi ...

s and deep-sea fish, to be specific, '' Poricthys''. Like the compound coelenterazine, it is an imidazopyrazinone and emits primarily blue light in the animals.

Fungi

Foxfire is the bioluminescence created by some species of fungi present in decaying wood. While there may be multiple different luciferins within the kingdom of

fungi A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from ...

, 3-hydroxy

hispidin Hispidin is a natural substance. It can also be synthesized. Hispidin 4-''O''-β-D-glucopyranoside can be found in ''Pteris ensiformis'' whereas hispidin derivatives, such as phellibaumins, can be found in the edible mushroom '' Inonotus xerantic ...

was determined to be the luciferin in the

fruiting bodies The sporocarp (also known as fruiting body, fruit body or fruitbody) of fungi is a multicellular structure on which spore-producing structures, such as basidia or asci, are borne. The fruitbody is part of the sexual phase of a fungal life cyc ...

of several species of fungi, including '' Neonothopanus nambi'', ''

Omphalotus olearius ''Omphalotus olearius'',Singer R (1948) In: ''Pap. Mich. Acad. Sci.'' 32: 133 ('1946'). commonly known as the jack-o'-lantern mushroom, is a poisonous orange gilled mushroom that to an untrained eye appears similar to some chanterelles. It is n ...

'', '' Omphalotus nidiformis'', and '' Panellus stipticus''.

Usage in science

Luciferin is widely used in science and medicine as a method of ''in vivo'' imaging, using living organisms to non-invasively detect images and in molecular imaging. The reaction between luciferin substrate paired with the receptor enzyme luciferase produces a catalytic reaction, generating bioluminescence. This reaction and the luminescence produced is useful for imaging such as detecting tumors from cancer or capable of measuring gene expression.

References

External links

* {{cite web , url = http://www.lifesci.ucsb.edu/~biolum/chem/detail1.html , title = Major luciferin types , date = 2009-01-09 , work = The Bioluminescence Web Page , publisher =

University of California, Santa Barbara The University of California, Santa Barbara (UC Santa Barbara or UCSB) is a public land-grant research university in Santa Barbara, California with 23,196 undergraduates and 2,983 graduate students enrolled in 2021–2022. It is part of the U ...

, access-date = 2009-03-06 Biological pigments Bioluminescence Fluorescent dyes Luciferins