Venom, marine organisms

There are a host of marine organisms capable of injuring the skin (Fisher 1995). The professional diver is usually aware of how to avoid these and is also protected by a dive suit and, often, gloves. Even so, dermatitis can result from envenomation of exposed skin by a wide range of jellyfish and anemones (Manowitz and Rosenthal 1979). The eruptions are usually linear and are caused by the venomous discharge of nematocysts present on tentacles and triggered by frictional contact. 

Tightly fitting rubber wetsuits Plastic and rubber mouthpieces Venom of marine organisms... 

Manowitz NR, Rosenthal RR (1979) Cutaneous-systemic reactions to toxins and venoms of common marine organisms. Cutis 23 450... 

Some of the articles dted are not limited to cone venoms but concern mollusks generally or neuropeptides extracted from marine organisms. The harpoons ejected by cones can pierce the plastic bags used to store them (Stanisic, 1987). 

Since organic chemistry began, the chemistry of natural products from terrestrial organisms such as plants and fungi has been studied intensively in contrast, marine species have received relatively little attention. However, in the last decade research in the field of marine products has increased substantially. The heightened interest in this area is attested by the appearance of the monumental treatise of Halstead on Poisonous and Venomous Marine Animals in 1965 108), Baslow s review on Marine Pharmacology in 1969 14) and Scheuer s recent book Chemistry of Marine Natural Products 160) in 1973. In addition Premuzic s review devoted to the Chemistry of Natural Products Derived from Marine Sources, was published in volume 29 of this series in 1971 (752). 

The precise composition of cone snail venom is species-specific with significant intraspecies variability. The venom is an extremely complex concoction (20-200 components) of modified peptides (conopeptides) that elicit a wide range of strong neurophysiological responses in a variety of organisms. The development of such extremely potent and biochemically diverse venom is likely to be an evolutionary adaptation designed to compensate for the lack of mobility of cone snails when compared to other marine predators. 

Toxins are natural venoms produced by the metabolic activities of living organisms. These compounds can be small molecules, peptides, or proteins and are capable of causing damage when introduce into the body. This definition includes a wide range of molecules with different structure and activity, such as mycotoxins, produced by fungus marine toxins, produced by dinoflagellates and venoms (peptidic toxins) secreted by some animals, such as snakes, scorpions, and bees. 

The polychaetes are almost exclusively marine, and the number of species is estimated at 10000. There has been much work on their primary and secondary metabolites. The numerous bristles serve as a means of locomotion, and for species of the family Amphinomidae, as defense organs that can inject venom at the slightest touch. Thus, the bristleworm Eurythoe complanata (marine fire-worm ), foimd in all tropical waters, secretes the quaternary ammonium salt complanine, which may produce the skin inflammation that occurs on physical contact with the worm (Nakamura et al, 2008). This inflammatory mechanism appears similar to that of Dogger Bank itch which is provoked by a sulfoxonium salt produced by a bryozoan (see Chapter 22). Later on, two new related compotmds, neocomplanines A and B were isolated from the same organism (Nakamura et al, 2010). 

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