Coelenterazine is a luciferin, a molecule that emits light after reaction with

oxygen Oxygen is a chemical element; it has chemical symbol, symbol O and atomic number 8. It is a member of the chalcogen group (periodic table), group in the periodic table, a highly reactivity (chemistry), reactive nonmetal (chemistry), non ...

, found in many aquatic organisms across eight

phyla Phyla, the plural of ''phylum'', may refer to: * Phylum, a biological taxon between Kingdom and Class * by analogy, in linguistics, a large division of possibly related languages, or a major language family which is not subordinate to another Phy ...

. It is the substrate of many luciferases such as '' Renilla reniformis'' luciferase (Rluc), ''Gaussia'' luciferase (Gluc), and photoproteins, including aequorin, and obelin. All these proteins catalyze the oxidation of this substance, a reaction catalogued EC 1.13.12.5.

History

Coelenterazine was simultaneously isolated and characterized by two groups studying the luminescent organisms sea pansy ('' Renilla reniformis'') and the

cnidarian Cnidaria ( ) is a phylum under kingdom Animalia containing over 11,000 species of aquatic invertebrates found both in fresh water, freshwater and marine environments (predominantly the latter), including jellyfish, hydroid (zoology), hydroids, ...

Aequorea victoria ''Aequorea victoria'', also sometimes called the crystal jelly, is a bioluminescent hydrozoan jellyfish, or hydromedusa, that is found off the west coast of North America. The species is best known as the source of aequorin (a photoprotein), and ...

'', respectively. Both groups independently discovered that the same compound was used in both luminescent systems. The molecule was named after the now-obsolete phylum coelenterata. Likewise, the two main metabolites – coelenteramide and coelenteramine – were named after their respective

functional groups In organic chemistry, a functional group is any substituent or moiety (chemistry), moiety in a molecule that causes the molecule's characteristic chemical reactions. The same functional group will undergo the same or similar chemical reactions r ...

. While coelenterazine was first discovered in ''

'', it was later shown that they do not synthesize coelenterazine, but obtain it through their diet, largely from crustaceans and copepods.

Occurrence

Coelenterazine is widely found in marine organisms including: * radiolarians *

ctenophore Ctenophora (; : ctenophore ) is a phylum of marine invertebrates, commonly known as comb jellies, that inhabit sea waters worldwide. They are notable for the groups of cilia they use for swimming (commonly referred to as "combs"), and they ar ...

s *

s such as ''

'', '' Obelia geniculata'' and '' Renilla reniformis'' *

squid A squid (: squid) is a mollusc with an elongated soft body, large eyes, eight cephalopod limb, arms, and two tentacles in the orders Myopsida, Oegopsida, and Bathyteuthida (though many other molluscs within the broader Neocoleoidea are also ...

such as '' Watasenia scintillans'' and '' Vampyroteuthis infernalis'' *

shrimp A shrimp (: shrimp (American English, US) or shrimps (British English, UK)) is a crustacean with an elongated body and a primarily Aquatic locomotion, swimming mode of locomotion – typically Decapods belonging to the Caridea or Dendrobranchi ...

such as '' Systellaspis debilis'' and '' Oplophorus gracilirostris'' *

copepod Copepods (; meaning 'oar-feet') are a group of small crustaceans found in nearly every freshwater and saltwater habitat (ecology), habitat. Some species are planktonic (living in the water column), some are benthos, benthic (living on the sedimen ...

s such as '' Pleuromamma xiphias'' and '' Gaussia princeps'' * chaetognaths *

fish A fish (: fish or fishes) is an aquatic animal, aquatic, Anamniotes, anamniotic, gill-bearing vertebrate animal with swimming fish fin, fins and craniate, a hard skull, but lacking limb (anatomy), limbs with digit (anatomy), digits. Fish can ...

including some Neoscopelidae and Myctophidae *

echinoderm An echinoderm () is any animal of the phylum Echinodermata (), which includes starfish, brittle stars, sea urchins, sand dollars and sea cucumbers, as well as the sessile sea lilies or "stone lilies". While bilaterally symmetrical as ...

s such as '' Amphiura filiformis'' The compound has also been isolated from organisms that are not luminescent, such as the Atlantic herring and several

species including '' Pandalus borealis'' and '' Pandalus platyuros''.

Biosynthesis

Biosynthesis of coelenterazine in ''Metridia'' starts from two molecules of

tyrosine -Tyrosine or tyrosine (symbol Tyr or Y) or 4-hydroxyphenylalanine is one of the 20 standard amino acids that are used by cells to synthesize proteins. It is a conditionally essential amino acid with a polar side group. The word "tyrosine" is ...

and one molecule of

phenylalanine Phenylalanine (symbol Phe or F) is an essential α-amino acid with the chemical formula, formula . It can be viewed as a benzyl group substituent, substituted for the methyl group of alanine, or a phenyl group in place of a terminal hydrogen of ...

, and some researchers believe this comes in the form of a cyclized "Phe-Tyr-Tyr" (FYY) peptide. Many members of the genus ''Metridia'' also produce luciferases that use this compound, some of which are secreted into extracellular space, an unusual property for luciferases.

Properties

Coelenterazine can be crystallized into orange-yellow crystals. The molecule absorbs light in the

ultraviolet Ultraviolet radiation, also known as simply UV, is electromagnetic radiation of wavelengths of 10–400 nanometers, shorter than that of visible light, but longer than X-rays. UV radiation is present in sunlight and constitutes about 10% of ...

and visible spectrum, with peak absorption at 435 nm in methanol, giving the molecule a yellow color. The molecule spontaneously oxidizes in aerobic conditions or in some organic solvents such as

dimethylformamide Dimethylformamide, DMF is an organic compound with the chemical formula . Its structure is . Commonly abbreviated as DMF (although this initialism is sometimes used for 2,5-dimethylfuran, dimethylfuran, or dimethyl fumarate), this colourless liqui ...

and DMSO and is preferentially stored in

methanol Methanol (also called methyl alcohol and wood spirit, amongst other names) is an organic chemical compound and the simplest aliphatic Alcohol (chemistry), alcohol, with the chemical formula (a methyl group linked to a hydroxyl group, often ab ...

or with an

inert gas An inert gas is a gas that does not readily undergo chemical reactions with other chemical substances and therefore does not readily form chemical compounds. Though inert gases have a variety of applications, they are generally used to prevent u ...

Synthetic coelenterazine derivatives

To improve its biophysical properties, derivatives of coelenterazine have been synthesized by means of different procedures including multicomponent strategies.

References

External links

Bioluminescence Page
showing major luciferin types.

External links

*{{Commonscatinline Bioluminescence Aminopyrazines Imidazopyrazines Lactams 4-Hydroxyphenyl compounds Luciferins

History

Occurrence

Biosynthesis

Properties

Synthetic coelenterazine derivatives

See also

References

External links

External links