Mussels saxitoxin from

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. 

In addition to these passive processes shellfish have been shown to actively modify the saxitoxins. Shimizu has shown (40) that scallops can remove both the N-l-hydroxyl and 11-hydroxysulfate groups from the saxitoxins. Sullivan has shown ( ) that enzymes in littleneck clams can remove the sulfamate or carbamate side chain, yielding the decarbamoyl toxins. This activity was not detected in either mussels or butter clams. With both sorts of modification the products are compounds that have higher potency and are likely to be bound in shellfish more strongly. 

Paralytic Shellfish Poisoning (PSP) was first determined to be a problem in 1942 after three people and many seabirds died from eating shellfish on the west coast of the United States, near the Columbia River. It is caused by the saxitoxin family (saxitoxin + 18 related compounds) produced by several species of Alexandrium dinoflagellates. The main contamination problems include mussels, clams, crabs, and fish of the Pacific Northwest and Northeast Atlantic. 

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. 

Inami, G.B. et al., Feasibility of reduction in use of the mouse bioassay Presence/absence screening for saxitoxin in frozen acidified mussel and oyster extracts from the coast of California with in vitro methods, J. AOACInt., 87, 1133, 2004. 

Saxitoxin, the best known example of this group, is a potent neurotoxin found in shellfish such as mussels, clams, and scallops. Saxitoxin is a sodium channel-blocking agent and is more toxic by inhalation than by other routes of exposure. Unlike oral intoxication with saxitoxin (paralytic shellfish poisoning), which has a relatively slow onset, inhala-tional intoxication with saxitoxin can be lethal in a few minutes. Saxitoxin could be used against our troops as an antipersonnel weapon, but because it cannot currently be chemically synthesized efficiently, or produced easily in large quantities from natural sources, it is unlikely to be seen as an area aerosol weapon on the battlefield. 

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. 

Cordycepin (3 -deoxyadenosine) is formed from adenosine by direct reduction. h) Saxitoxin. Certain dinoflagellates form saxitoxin, which also accumulates in marine invertebrates, e.g., in mussels and in the Alaskan clam, which use dinoflagellates as food source. Saxitoxin is a very active neurotoxin for mammals and in the last years caused repeatedly intoxication of human beings. 

Dell Aversano C, Walter JA, Burton IW, Stirling DJ, Fattorusso E, Quilliam MA (2008) Isolation and structure elucidation of new and unusual saxitoxin analogues from mussels. J Nat Prod 71 1518-1523. doi 10.1021/np800066r... 

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