Butter clams, toxicity

As mentioned above we obtained most of the poison for our chemical and biological work from the Alaska butter clam. However our search for a dinoflagellate or any other poisonous organism in the water as a source of the poison in the clams was never definitely accomplished. In 1948, and in some years following, along with a survey for toxic butter clams in Southeastern Alaska by the staff at the Fishery Products Research Laboratory at Ketchikan, 1 collected plankton in areas where the clams were found to be toxic. Mouse assays of the plankton showed no toxicity. Microscopic examination of the water in these areas showed heavy growth of microscopic plankton but little or no evidence of... 

Work on the chemical structure and properties of the poisons from Alaska butter clam siphons, the hepatopancreas of California mussels, and axenic cultures of G. catenella carried on in the Biological Laboratories and with Rapoport at the University of California definitely established that the sea mussel did not alter the poison obtained from G. catenella. The poison from all three sources had identical structures (31). The situation with the Alaska butter clam may be different however in light of the different saxitoxin derivatives recently found in the dinoflagellates in that region. Perhaps the clam converts the sulfo and sulfate derivatives to the more toxic saxitoxin. 

Figure 6. A-Chromatogram of toxic butter clam extract showing the presence of the PSP toxins. B-Chromatogram of extract from non-toxic (bioassay) mussels showing the presence of a trace of GTX II, GTX III, and C. Conditions as in Table I with gradient shown in Figure 4.

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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