Vargula

THE OSTRACOD CYPRIDINA (VARGULA) AND OTHER LUMINOUS CRUSTACEANS... 

The Ostrocod Cypridina (Vargula) and other Luminous Crustaceans 63... 

Kato, S., Oba, Y., Ojika, M., and Inouye, S. (2004). Identification of the biosynthetic units of Cypridina luciferin in Cypridina (Vargula) hilgen-dorfii by LC/ESI-TOF-MS. Tetrahedron 60 11427-11434. 

Kobayashi, K., et al. (2000). Purification and properties of the luciferase from the marine ostracod Vargula hilgendorfii. In Case, J. F., et al. (eds.), Biolumin. Chemilumin.,Proc. Int. Symp., 11th, pp. 87-90. World Scientific, Singapore. 

Kornicker, L. S., and Baker, J. H. (1977). Vargula tsujii, A new species of luminescent Ostracoda from lower and southern California (Myodocopa Cypridininae). Proc. Biol. Soc. Washington 90 218-231. 

Maeda, Y., et al. (1997). Engineering of functional chimeric protein G-Vargula luciferase. Anal. Biochem. 249 147-152. 

Thompson, E. M., Nafpakdds, B. G., and Tsuji, F. I. (1987). Induction of bioluminescence in the marine fish, Porichthys, by Vargula (crustacean) luciferin. Evidence for de novo synthesis or recycling of luciferin. Pho-tochem. Photobiol. 45 529-533. 

Toya, Y. (1992). Chemistry of Vargula (formerly Cypridina) bioluminescence. Nippon Nogei Kagaku Kaishi 66 742-747. 

In Renilla the coelenterazine is stored as a coelenterazine sulfate, possibly having the structure shown. To convert this storage form to the active luciferin the sulfo group is transferred onto adenosine 3, 5 -bisphosphate to form 3 -phosphoadenosine 5 -phosphosulfate, the reverse of step d of Eq. 17-38. Tire luciferin of the ostracod crustacean Vargula hilgendorfii has a structure (Fig. 23-51) close to that from Renilla. 

In Vargula (formerly Cypridina) the luciferin and lu-ciferase are produced in separate glands and are secreted into the surrounding water where they mix and produce a bright cloud of light.671... 

In the case of Vargula luciferin the expected incorporation of one atom of lsO into C02 was observed, but with firefly and Renilla luciferins no lsO entered the C02. In these two cases, a somewhat different mechanism may hold. 

Cypridina luciferin is an imidazopyrazinone involved in the bioluminescence of the crustacean Cypridina (Vargula) hilgendotfii. The first total synthesis of this natural product was achieved by Kishi in 1966, which was followed by that of White and Karpetsky in 1971. Most recently, Nakamura et al. developed a convenient, direct procedure for this synthesis, employing Suzuki coupling (Eq. (36)) [67]. 

We have developed a new methodology for the feeding of the labeled amino acids to V. hilgendorfii. In this report we describe that L-Arg, L-Trp, and L-Ile were effectively incorporated into Vargula luciferin, therefore, it was clarified to be biosynthesized from these amino acids. 

Figure 1. Vargula luciferin and its supposed components in biosynthesis...

Vargula individuals were collected at Shima County (Pacific coast of Mie Prefecture, Japan) and were kept in aquariums before the incorporation experiment. Materials... 

L-Arg (guanido- N2, N, >98%) hydrochloride, L-Trp (indole-Ds, D, 98%), and L-Ile (Uniform- Ce, C, 98%) were purchased from Cambridge Isotope Laboratories, Inc. The enrichment of these compounds (>95%) was reconfirmed by MALDI-TOFMS analysis. All other chemicals were of highest grade commercially available. Complete release of luciferin (1) from Vargula by electric stimulation The individuals were put into 10 mL of artificial seawater in a Petri dish, which was equipped with two carbon electrodes (spare lead). In order to release the luciferin completely, AC 30 V was charged to the electrodes for one second repeatedly (20-30 times), until no bioluminescence was observed after the pulse stimulation. Preparation of the formula bait... 

After the electrical stimulation, Vargula individuals were cultured by feeding small portion of the bait every day for 14-15 d. In the case of labeled L-Trp or L-Arg feeding, 10 individuals were fed together in 10 mL of artificial seawater in a Petri dish. For L-Ile incorporation, 24-well plates were used to culture each Vargula individually in 1 mL of artificial seawater. 

By repeated electrical stimulation Vargula released almost of all luciferin (1) and luciferase stored inside the body into the seawater with light emission. Therefore, after this treatment 1 would be bio-synthesized from amino acids in the formula bait. Since we added ATP, which is a feeding stimulating substance for Vargula, to the... 

As the incorporation of L-Ile could not be proven by analysis of 3, 1 was isolated from the freeze-dried Vargula whole bodies (13-21 individuals), and analysed by MS. When [ Cel-L-Ile was fed, 1 showed its molecular ion peaks at miz 406 (Mh-H) and miz 412 (labeled) and the peak intensity ratio of 412/406 indicate very high incorporation rate of 42% (Fig. 3). 

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