Luciferins coelenterate

The name of coelenterazine. We suggested calling the new luciferin coelenterazine (Shimomura and Johnson, 1975b), although Inoue et al. (1976) named it Watasenia preluciferin. The compound has been called by various other names, such as coelenterate luciferin, coelenterate-type luciferin, Oplopborus luciferin, and Renilla luciferin. However, these two-word chemical names are cumbersome to use and inconvenient when applying a chemical prefix or suffix. Currently, the name coelenterazine is widely and commonly used. 

Goelenterate. Coelenterates Penilla reformis (sea pansy) -cradViequoreaforskalea (jelly fish) produce bioluminescence by similar processes (223). The basic luciferin stmcture is (49) (224) and excited amide (50) is the emitter. The stmctural relationship to Varela is evident. A stmctural analogue where R = CH is active ia bioluminescence. The quantum yield is about 4% (223), with at 509 nm (56). This reaction iavolves a charge transfer between green fluorescent proteia and the excited-state coelenterate oxylucifetin. 

Hart, R. C., Stempel, K. E., Boyer, P. D., and Cormier, M. J. (1978). Mechanism of the enzyme-catalyzed bioluminescent oxidation of coelenterate-type luciferin. Biochem. Biophys. Res. Commun. 81 980-986. 

Usami, K., and Isobe, M. (1996). Chemiluminescent characters of hydroperoxide and dioxetanone of coelenterate luciferin analog prepared by low-temperature photooxygenation. Chem. Lett. 3 215-216. 

Usami K, Isobe M. Low-temperature photooxygenation of coelenterate luciferin analog — synthesis and proof of 1,2-dioxetanone as luminescence intermediate. Tetrahedron 1996 52 12061-90. 

Figure 1 Structures of luciferins (A) limpet luciferin (e.g., Latia) (B) firefly luciferin (e.g., Photinus) (C) dinoflagellate luciferin (e.g., Gonyaulax)-, (D) coelenterate luciferin (e.g., Renilla, Aequorea) (E) bacterial luciferin (e.g., Vibrio, Photobacterium).

Luciferin-binding protein -I- coelenterate luciferin —> luciferin-binding protein luciferin [VI]... 

Acridan active esters are particularly efficient, quantum yields in the region of 10% being obtainable. The reaction is entirely analogous to that of firefly and coelenterate luciferins. Dipolar aprotic solvents give the best results and there is good evidence for all the steps shown [21] ... 

Although these organisms are not related (the first is an ostracod crustacean and the second is a group of organisms of which the jellyfish is a member), they share the same chemiluminescence mechanism. The luciferins are not identical but the central imidazopyrazine nucleus is common to both. Indeed the most likely biosynthesis for each is the cyclisation of a tripeptide, so that only the amino acid side chains are different. Coelenterate luciferin is also known as coelenterazine and is... 

Thus the electron donating properties of the essential phenoxide ion in firefly luciferin, and the adjacent N-atoms of coelenterate and Cypridina luciferins, are seen to be important in explaining both the reaction rate and the excitation mechanism. 

Very similar ideas can be applied to Cypridina and coelenterate luciferin, but excitation in the bacterial system seems at present less understandable. 

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