Marine neurotoxins

Tetrodotoxin (TTX) is a potent neurotoxin. Its name derives from Tetraodontiformes, an order that includes pufferfish, porcupinefish, ocean sunfish, and triggerfish; several of these species carry the toxin. Although tetrodotoxin was discovered in these fish, it is found in several other animals (e.g., in blue-ringed octopuses, rough-skinned newts, and moon snails). It is also produced by certain infectious or symbiotic bacteria like Pseudoalteromonas, Pseudomonas, and Vibrio as well as other species found in symbiotic relationships with animals and plants.

Saxitoxin (STX) is a potent neurotoxin and the best-known paralytic shellfish toxin. Ingestion of saxitoxin by humans, usually by consumption of shellfish contaminated by toxic algal blooms, is responsible for the illness known as paralytic shellfish poisoning (PSP).

chemical compound

Maitotoxin (MTX) is an extremely potent toxin produced by Gambierdiscus toxicus, a dinoflagellate species. Maitotoxin has been shown to be more than one hundred thousand times as potent as the nerve agent VX. Maitotoxin is so potent that it has been demonstrated that an intraperitoneal injection of 130 ng/kg was lethal in mice. Maitotoxin was named from the ciguateric fish Ctenochaetus striatus—called "maito" in Tahiti—from which maitotoxin was isolated for the first time. It was later shown that maitotoxin is actually produced by the dinoflagellate Gambierdiscus toxicus.

natural marine acid present in some seaweed

thumb|300px|right|class=skin-invert-image|Chemical structure of the ciguatoxin CTX1B Ciguatoxins are a class of toxic polycyclic polyethers found in fish that cause ciguatera.

Eledoisin is an undecapeptide of mollusk origin, belonging to the tachykinin family of neuropeptides.

Nemertelline is a neurotoxic tetra-pyridine compound originally found in the marine ribbon worm Amphiporus angulatus. These worms produce a variety of toxins which are used both in hunting down prey and in defending themselves from predators. Interest in potential application of this compound as an antifouling agent for boats and other marine installations has led to attempts to produce it synthetically by convenient routes. This compound is highly toxic to crustaceans but not mammals and is similar to the plant alkaloid nicotelline in structure.

Yessotoxins are a group of lipophilic, sulfur bearing polyether toxins that are related to ciguatoxins. They are produced by a variety of dinoflagellates, most notably Lingulodinium polyedrum and Gonyaulax spinifera.

Brevetoxin (PbTx), or brevetoxins, are a suite of cyclic polyether compounds produced naturally by a species of dinoflagellate known as Karenia brevis. Brevetoxins are neurotoxins that bind to voltage-gated sodium channels in nerve cells, leading to disruption of normal neurological processes and causing the illness clinically described as neurotoxic shellfish poisoning (NSP). Although brevetoxins are most well-studied in K. brevis, they are also found in other species of Karenia and at least one large fish kill has been traced to brevetoxins in Chattonella.