Palythoa

Na+/K+-ATPase. Figure 2 Specific Inhibitors of Na+/K+-ATPase. (a) Endogenous cardiac glycosides identified in mammals. Substances with a 5-membered lactone at position C17 of the steroid moiety are referred to as cardenolides, those with a 6-membered lactone as bufadienolides. (b) Palytoxin (C P NsO ) produced by corals of the genus Palythoa. 

Palytoxin isolated from zoanthids Palythoa spp. is known to be extremely lethal (0.5 fig/kgy mouse, i.p.) and to have the most complicated natural product structure (Figure 4) ever elucidated (13,14). The toxin was later revealed to be a potent tumor promoter (15). Yet, health risks due to the toxin have remained unclear, as the zoathids are the most unlikely organisms to be regarded as foodstuff. Recently, however, data are being compiled to indicate the wide distribution of this toxin among marine biota. 

Distribution. The first indication of the occurrence of palytoxin in fish was presented in 1969 (16). The filefish Altera scripta belonging to family Monacathidae was traditionally known in Okinawa, Japan, to contain a toxic substance in the gut and, thus, to kill pigs when fed to them. The presence of fragments of Palythoa sp. in the guts and the resemblance in solubility between the fish toxin and palytoxin led the authors to a conclusion that the toxic principle in the filefish viscera was palytoxin. Incidence of human intoxication due to eating the filefish was not confirm. ... 

Many environmental toxins interact with specific cellular receptors, including enzymes, ion channels and ion pumps, and thus provide natural tools for the study of cellular signalling pathways. Palytoxin, a compound isolated from the coelen-terate of genus Palythoa, is one such useful and intriguing compound. The structure of palytoxin was first determined in 1981 independently by Hirata (7) and Moore (2). As one of the most potent marine toxins known, palytoxin has been studied in a variety of systems ranging from erythrocytes to neurons. As a tumor promoter of the non 12-O-tetradecanoylphorbol-13-acetate (TPA) type, palytoxin can also be studied in the context of a growth control system. 

Materials. I-EGF was either made by iodinating mouse EGF (Biomedical Technologies Inc.) by the chloramine T method, to a specific activity of approximately 1-2 Ci/ xmol, using Na- I (Amersham) or purchased from New England Nuclear. Phorbol diterpene esters were purchased from Sigma. Palytoxin was isolated from Palythoa tuberculosa as previously described (1). 

Palytoxin (PTX), isolated from the zanthid Palythoa species, caused a rapid contraction followed by a slow phasic contraction of the guinea pig vas deferens. The second component of PTX-induced contraction was markedly inhibited by adrenergic blocking agents, whereas the first component was blocked by ouabain. In pheochromocytoma cells,... 

Figure 1. Structure of palytoxin, isolated from P, tuberculosa (3), immunogen (bovine albumin). The structures of the palytoxins from different Palythoa species vary in the hemiketal ring at position C55 (2, 3).

This work was supported by Grant GM 27256 from the National Institutes of Health and Grant DA 02507 from the National Institute of Drug Abuse. LL. is an American Cancer Society Research Professor of Biochemistry (Award PRP-21). H.V.V. is the recipient of a Research Career Award (5K6-AI-2372) from the National Institute of Allergy and Infectious Disease. We thank Dr. Y. Hirata of Meijo University for generous gifts of palytoxin isolated from Palythoa tuberculosa. We thank Dr. T. Yasumoto, Tohoku University, Sendai, Japan, for the maitotoxin preparation. We thank also Jeffrey A. Bessette and Nancy Worth for their technical assistance and Inez Zimmerman for preparation of the manuscript. 

CAS 11077-03-5 (from Palythoa caribaerum) 77734-92-0 (from Palythoa toxica) 77734-91-9 (from Palythoa toxica)... 

Rapid-acting neurotoxin that causes irreversible depolarization of neural and muscular tissue by an unknown mechanism. It has a very potent effect on coronary arteries and death may result from constriction of the blood vessels of the heart. It is a solid obtained from bacterium associated with soft corals (Palythoa caribaerum and Palythoa toxica). It is soluble in water and alcohol, and stable to heat. 

Cronan, J.M., Jr. Davidson, T.R. Singleton, F.L. Colwell, R.R. Cardellina II, J.H. (1998) Plant growth promoters isolated from a marine bacterium associated with Palythoa sp. Nat. Prod. Lett., 11, 271-8. 

Additional biological properties have been reported from toxins of marine origin, such as actin-inhibitory activity [527,528], and inactivation of a serotonin-gated ion channel [529], More recently, marine toxins have also been identified from sea cucumbers [530], and coral reef animals [531], These toxins, which have been detected in zoanthid species of the genus Palythoa, also occur in various marine organisms living in dose association with zoanthid colonies, e g., sponges, soft corals, mussels and crustaceans. 

Carballeira NM, Reyes M (1995) Identification of a New 6-Bromo-5,9-eicosadienoic Acid from the Anemone Condylactis gigantea and the Zoanthid Palythoa caribaeorum. J Nat Prod 58 1689... 

Miralles, J., Diop, M., Ferrer, A., and Kornprobst, J.-M., Fatty acid composition of five Zoantharia from the Senegalese coast Palythoa dartevellei Pax, P. monodi Pax, P. variabilis Duerden, P. sene-galensis Pax and their associated Zooxanthellae, and P. senegambiensis Carter and its commensal, the decapoda Diogenes ovatus Miers, Comp. Biochem. Physiol., 94B, 91, 1989. 

Gadus morhua97 Auxis thazard76 Palythoa tuberculosa204 Chondrus yendoP4 Palythoa tuberculosa83... 

Pocillopora eydouxi95 Palmaria palmata205 Palythoa tuberculosa75 85 Pocillopora eydouxi95... 

Hirata, Y., Uemura, D., Ueda, K., and Takano, S., Several compounds from Palythoa tuberculosa (Colenterata), Pure Appl. Chem., 51, 1875, 1979. 

Ito, S. and Hirata, S., Isolation and structure of a mycosporine from the zoanthid Palythoa tuberculosa, Tetrahedron Lett., 1977, 2429, 1977. 

The versatility of the enolone ester 27 is illustrated by a variety of synthetically useful addition reactions, e. g. with lithium alkyls, Grignard reagents and cyclopentadiene in a Diels-Alder type fashion (40, 48, 49), but, most notably, it could be utilized for straightforward syntheses of the marine natural products (-)-bissetone (28), a metabolite from the Gorgonian soft coral Briareum polyanthes (50), and (-)-palythazine (29), an unusual dipyranopyrazine isolated from the salt water invertebrate Palythoa tuberculosa (51). 

Palytoxm] Palythoa spp. (zooanthid coral) Na+, K+-ATPase (0.1)- opens... 

Figure 5.1. Proposed structure of palytoxin from a Tahitian Palythoa sp. (1A). The two paiytoxins from Hawaiian P toxica are the related C-55 hemiketais (partiai structures 1B and 1C). Reproduced with permission from Moore and Bartolini 1981, American Chemical Society.

Palytoxin from the Tahitian Palythoa has a molecular form of Cj29H22iN30j4 (Mj. 2659). On the other hand, palytoxin from P. toxica has a molecular form of C,29H223N3054 (M. 2611), with two possible structures (Fig. 5.1) that differ from the former in the C-55 hemiketal ring. Palytoxin from the Hawaiian P. tuberculosa is a mixture of the three palytoxins from the Tahitian Palythoa and P. toxica (Mooie and Bartolini 1981). The two components in palytoxin from the Okinawan P. tuberculosa (Mj. 2681 Macfarlane et al. 1980) may be the related C-54 ketal and hemiketal (Moore and Bartolini 1981). The palytoxin from P. caribaoreum has a molecnlar mass of 2680, while the palytoxin-like substance isolated from Lophozozymus pictor crab, which showed a very similar positive ion MS profile, was estimated to possess a molecular mass of 2681.0 Da (Lau et al. 1995). 

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