Firefly chemiluminescence mechanism

The theoretical yield is approached by the firefly reaction, discussed later, which is reported to have of 88% (5). In practice, however, most chemiluminescent reactions are inefficient, withQc values on the order of 1% or much less. The factors influencing yields can be discussed in terms of a generalized three-step chemiluminescent mechanism (6) ... 

Analogously to the firefly luciferin/luciferase system, the general chemiluminescence mechanism postulated for 9-carboxyacridinium derivatives proposes the 1,2-dioxetanone 45 as high-energy intermediate However, this 1,2-dioxetanone is the only intermediate that has not yet been isolated . The cleavage of the peroxidic ring presumably results in the release of CO2 and the formation of an acridan residue in its electronically excited state (Scheme 32). 

A review of chemiluminescent and bioluminescent methods in analytical chemistry has been given by Kricka and Thorpe. A two-phase flow cell for chemiluminescence and bioluminescencc has been designed by Mullin and Seitz. The chemiluminescence mechanisms of cyclic hydrazides, such as luminol, have been extensively analysed. " Fluorescence quantum yields of some phenyl and phenylethynyl aromatic compounds in peroxylate systems have been determined in benzene. Excited triplet states from dismutation of geminate alkoxyl radical pairs are involved in chemiluminescence from hyponitrite esters. Ruorophor-labelled compounds can be determined by a method based on peroxyoxalate-induced chemiluminescence. Fluorescence and phosphorescence spectra of firefly have been used to identify the multiplicity of the emitting species. " The chemiluminescence and e.s.r. of plasma-irradiated saccharides and the relationship between lyoluminescence and radical reaction rate constants have also been investigated. Electroluminescence from poly(vinylcarbazole) films has been reported in a series of four... 

Later, fireflv oxyluciferin was successfully synthesi2ed (403. 408) and has been isolated and identified in firefly lanterns (luciola cruaciata) after the lanterns were treated with pyridine and acetic anhydride to prevent decomposition (409). In 1972, Suzuki and Goto firmly established that oxyluciferin is involved in the bioluminescence of firefly lanterns and in the chemiluminescence of firefly luciferin (403. 410).. A. mechanism involving a four-membered ring cyclic peroxide has been proposed for the reaction (406. 411). However, it was not confirmed by 0 -labelinE experiments (412). 

One is the concerted decomposition of a dioxetanone structure that is proposed for the chemiluminescence and bioluminescence of both firefly luciferin (Hopkins et al., 1967 McCapra et al., 1968 Shimomura et al., 1977) and Cypridina luciferin (McCapra and Chang, 1967 Shimomura and Johnson, 1971). The other is the linear decomposition mechanism that has been proposed for the bioluminescence reaction of fireflies by DeLuca and Dempsey (1970), but not substantiated. In the case of the Oplopborus bioluminescence, investigation of the reaction pathway by 180-labeling experiments has shown that one O atom of the product CO2 derives from molecular oxygen, indicating that the dioxetanone pathway takes place in this bioluminescence system as well (Shimomura et al., 1978). It appears that the involvement of a dioxetane intermediate is quite widespread in bioluminescence. 

McElroy, W. D., Seliger, H. H., and White, E. H. (1969) Mechanism of bioluminescence, chemiluminescence and enzyme function in the oxidation of firefly luciferin. Photochem Photobiol. 10, 153-170. 

The chemiluminescence of dioxetanones is of particular interest due to their postulated intermediacy in several bioluminescence reactions, including that of the firefly, the sea pansy Renilla, and the ostracod crustacean Cypridina (Fig. 4). The generalized mechanism for these bioluminescence reactions (22),... 

Figure 4-11. Proposed mechanism for (a) bioluminescence and (b) chemiluminescence of the firefly [126]. (c) micro-environment mechanism [136-138, 147], and (d) our mechanism proposed in this study [131]...

Nakatani N, Hasegawa J, Nakatsuji H. Red light in chemiluminescence and yellow-green light in bioluminescence Color-tuning mechanism of firefly, Photinus pyralis, studied by the symmetry-adapted cluster-configuration interaction method. J Am Chem Soc 2007 129 8756-65. 

The quenching of peroxidized luminol chemiluminescence by reduced pyridine nucleotides has been reported. Neither superoxide nor hydroxyl radical scavengers were found to quench the chemiluminescence of luminol in the presence of horseradish peroxidase and H2O2. Both chemi- and bio-luminescence of firefly luciferin have been investigated and a dioxetanone mechanism proposed for the light-producing pathway. ... 

Fireflies and many other animals emit radiation by chemiluminescence. In this process, chemicals mix and produce light as one of the products of reaction. Many solids emit light when crushed, a manifestation of triboluminescence. There are no general mechanisms for luminescence, and each type needs to be treated independently. 

Fig. 7 Chemical functionalities of the bioluminescence phenomenon (a), neutral and ionic forms of the firefly oxyluciferin molecule (b) and main differences of the chemiluminescence and fluorescence phenomena of a model coelenteramide based on mechanisms and geometrical...

Firefly luciferin (111 R = R = H, X = OH) and a number of its analogues were synthesized by previously established reaction sequences from a variety of substituted 2-cyanobenzothiazoles (109) and cysteines (110). Amongst others, homoluciferin (112) and 5, 7 -dimethyl-luciferin (113) are accessible in this way. Their adenylates were produced by the condensation of the free acids with adenosine monophosphate in the presence of dicyclohexylcarbodi-imide. These were used in detailed spec-trophotometric studies of their chemiluminescence (initiated by bases), their fluorescence, and their bioluminescence under the influence of luciferase the possible mechanisms of these processes were discussed. ... 

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