Lophozozymus Palytoxin

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). 

Shortly thereafter, scientists began the tedious process of isolating the poisonous compound from this natural source. Palytoxin was finally isolated in pure form in 1971 at the University of Hawai i at Manoa, and its structure determined simultaneously by two different research groups in 1981. In 1994, Professor Yoshito Kishi and co-workers at Harvard University synthesized palytoxin in the laboratory. Over the last 20 years, palytoxin has also been isolated from marine animals like the red mosaic crab Lophozozymus pictor, which lives in close association with, and presumably feeds on, Palythoa (Figure 2). 

The red mosaic crab Lophozozymus pictor inhabits the coral reefs of the Philippines, Singapore, and Southeast Asia. Although palytoxin produces no adverse effects on these crabs, human fatalities from ingesting L pictor have been reported. 

Lau, C.O. et al., Lophozozymus pictor toxin a fluorescent structural isomer of palytoxin, Toxicon 33, 1373, 1995. 

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