Clam poisoning, Gonyaulax

Synonyms Mussel poison Clam poison Paralytic shellfish poison Gonyaulax toxin STX... 

Tetradotoxin is a potent neurotoxin isoiated from the ovaries and liver of many species of Tetradodontidae, especiaiiy the Japanese fugu (or puffer fish). Saxitoxin is a mussel or clam poison produced by certain marine dinoflagellates, Gonyaulax catenella or G. tamarensis, the consumption of which cause the mussels or clams to become poisonous. These poisonous shellfish were connected to a toxic red tide environmental condition on the coastal region of California in early 1970. Batrachotoxin is a cardiotoxic and neurotoxic steroid isolated originally from the poison dart frog, Phyllobates terribilis. It is a lipid soluble neurotoxin that is at least 10-fold more toxic than tetradotoxin. 

The discovery of the relationship of G. catenella to poisonous shellfish by Sommer, Whedon and associates led Canadian investigators Needier (3) and Prakash (4) to the discovery that Gonyaulax tamarensis (var. excavata) caused clams and scallops along the northeast coast of North America and the northeast coast of England to become poisonous. 

Saxitoxin is an alkaloid of nonplant origin. It is the neurotoxic constituent of dinoflagel-lates (Gonyaulax catenella and G. excavata) the so-called red tide found along the U.S. coast. Shellfish, clams, and scallops consume this and become extremely poisonous for human consumption. 

The paralytic poison produced by the dinoflagellate Gonyaulax catenella in axenic culture has been isolated in pure form by Schantz et al. (1966). A study of its chemical, physical, and biological properties established that it is identical in chemical structure to saxitoxin, the poison isolated from toxic Alaska butter clams (Saxidomas giganteus) and to the poison isolated from toxic California sea mussels Mytilus californiaus). Infrared spectra were given for G. catenella poison and the mussel poison. 

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