Tetrodotoxin - Sources in Nature

Sources in Nature

Tetrodotoxin has been isolated from widely differing animal species, including western newts of the genus Taricha (where it was formerly termed "tarichatoxin"), pufferfish, toads of the genus Atelopus, several species of blue-ringed octopuses of the genus Hapalochlaena (where it was called "maculotoxin"), several sea stars, certain angelfish, a polyclad flatworm, several species of Chaetognatha (arrow worms), several nemerteans (ribbonworms) and several species of xanthid crabs. The toxin is variously used as a defensive biotoxin to ward off predation, or as both a defensive and predatory venom (the octopuses, chaetognaths and ribbonworms). Tarichatoxin and maculotoxin were shown to be identical to tetrodotoxin in 1964 (by Mosher et all)and 1978, respectively. The toxin is produced by bacteria within blue-ringed octopuses. The most common bacteria associated with TTX production are Vibrio bacteria, with Vibrio alginolyticus being the most common species. Pufferfish, chaetognaths, and nemerteans have been shown to contain Vibrio alginolyticus and TTX. The link between these facts and production of TTX in animals has not been firmly established, and there remains much debate in the literature as to whether the bacteria are truly the source of TTX in animals.