Cypridina luciferin structure

Improved purification method of Cypridina luciferin. The purification of Cypridina luciferin became remarkably simple and easy after some of the properties of this substance were known. The following method was used to obtain the large quantity of luciferin needed for the study of its chemical structure. The method consists of three steps and takes less than eight hours to obtain crystallized luciferin. 

Chemical structure. The structure of the free base of Cypridina luciferin (C22H27ON7, Mr 405.50) was determined by Kishi et al. (1966a,b) as shown below (A) its sec-butyl group is in the same configuration as in L-isoleucine. The structure of oxyluciferin reported by the same authors contained an error, and the structure was corrected later as shown in Fig. 3.1.8 (McCapra and Chang, 1967 Stone, 1968). 

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. 

Coelenteramide and coelenterazine. The structure of AF-350 contains the same aminopyrazine skeleton as in Cypridina etioluciferin and oxyluciferin (Fig. 3.1.8), suggesting that the bioluminescence reaction of aequorin might resemble that of Cypridina luciferin. To investigate such a possibility, we prepared the reaction product of aequorin luminescence by adding Ca2+ to a solution of aequorin. The product solution (blue fluorescent) was made acidic, and extracted with... 

Hirata, Y., Shimomura, O., andEguchi, S. (1959). The structure of Cypridina luciferin. Tetrahedron Lett., pp. 4-9. 

Shimomura, O. (1960). Structure of Cypridina luciferin, II. J. Chem. Soc. Japan, Pure Chem. Section 81 179-182. 

FMNH2 requirement in bacterial luminescence Crystallization of Cypridina luciferin Crystallization of firefly luciferin Cypridina luciferin in fishes the first cross reaction discovered Structure of firefly luciferin Discovery of aequorin and GFP (green fluorescent protein) Structure of Cypridina luciferin Concept of photoprotein Structure of Latia luciferin Dioxetanone mechanism proposed in firefly and Cypridina luminescence... 

The structure of Cypridina luciferin was established by analysis of spectroscopic data, chemical degradations, extensive MS analysis, and total synthesis [41—44]. Cypridina luciferin is biosynthesized from L-tryptophan, L-arginine, and L-isoleudne [45,46]. Distomadines A (24) and B (25) have been isolated from the asddian Pseudodistoma aureum and were not adive in antifungal, antiviral, anti-inflammatory, and anti-mycobacterial bioassays [47]. 

The successful crystallization developed into the elucidation of the structures of Cypridina luciferin and its luminescence reaction products in 1966. That information made it possible to determine the structure of the aequorin luminophore several years later. 

Figure 1. Luminescence reactions of Cypridina luciferin and aequorin, in which Cypridina luciferin is oxidized to oxyluciferin and etioluciferin, whereas aequorin is decomposed into coelenteramide (CLA), CO2 and Ca -bound apoaequorin. Note the structural resemblance between AF-350 and etioluciferin.

Kishi Y, Goto T, Hirata Y, Shimomura O, Johnson FH. Cypridina bioluminescence I structure of Cypridina luciferin. Tetrahedron Lett. 1966 3427-36. 

Toya Y, Nakatsuka S, Goto T. Structure of Cypridina luciferinol, Reversibly oxidized Cypridina luciferin . Tetrahedron Lett 1983 51 5753-6. 

Goto T, Inoue S, Sugjura S, Nishikawa K, Isobe M, Abe Y. Cypridina bioluminescence V. Structure of emitting species in the luminescence of Cypridina luciferin and its related compounds. Tetrahedron Lett 1968 37 4035-8. 

This ring system has also been called l,3a,6-triazaindene and numbered as in formula 1. A third alternative numbering system (2) has also been used on one occasion. Partly reduced derivatives of imidazo[l,2-a]pyrazine have been referred to as imidazo[l,2-a]piperazines and others, as imidazolino[l,2-a]pyrazines. The majority of papers on this heterocycle are of recent origin and concern the structure and oxidation products of Cypridina luciferin, a bioluminescent substance isolated from Cypridina hilgendorfii, a small crustacean. 

Interestingly, crystalline salts of Cypridina luciferin (18) have been described as possessing two forms with different colors. " The color differences have been interpreted as indicating that the brilliant orange dihydrochloride has structure 19 and the faint brown dihydrobromide has structure 20. In solution both salts are orange yellow, corresponding to the protonated forms 19 and 12. 

Cypridina luciferin, in the presence of oxygen and the enzyme Cypridina luciferase, is oxidized with emission of light to give products called oxyluciferin and etioluciferin. On the basis of PMR and mass spectra the structure 21 was assigned to oxyluciferin. This is now known to be incorrect. Work on simple analogues of luciferin in aprotic solvents showed that oxidation of compounds such as 22 and 11 was accompanied... 

Kishi, Y., T. Goto, Y. Hkata, O. Shimomura, and F. H. Johnson Cypridina Bioluminescence I. Structure of Cypridina Luciferin. Tetrahedron Letts 1966, 3427. 

Mshi, Y, Goto, T Hirata, Y, Shimomura, 0 and Johnson, F.H. (1966a) Cypridina bioluminescence I. Structure of Cypridina luciferin. Tetrahedron Lett., 7, 3427-3436. 

These light-producing oxidations are quite different reactions in each of the three most thoroughly studied organisms, Cypridina, bacteria, and fireflies (382,566,567,569,709,761). The structures of the two luciferins, LHk and LHjf, and of their oxidation products (oxyluciferins , 568), and the fate of the long-chain fatty aldehyde which acts as cofactor in bacterial luminescent oxidation of FMNH, are all unknown. Each luminescent system requires molecular oxj en and a potential source of electrons, in common with mixed function oxidases, but the significance of these characteristics in terms of oxidase classification remains to be determined. 

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