Oxytetracycline is a broad-spectrum tetracycline antibiotic, the second of the group to be discovered.
Nonribosomal peptides (NRP) are a class of peptide secondary metabolites, usually produced by microorganisms like bacteria and fungi. Nonribosomal peptides are also found in higher organisms, such as nudibranchs, but are thought to be made by bacteria inside these organisms. While there exist a wide range of peptides that are not synthesized by ribosomes, the term nonribosomal peptide typically refers to a very specific set of these as discussed in this article.
Okadaic acid, C44H68O13, is a toxin produced by several species of dinoflagellates, and is known to accumulate in both marine sponges and shellfish. One of the primary causes of diarrhetic shellfish poisoning, okadaic acid is a potent inhibitor of specific protein phosphatases and is known to have a variety of negative effects on cells. A polyketide, polyether derivative of a C38 fatty acid, okadaic acid and other members of its family have shined light upon many biological processes both with respect to dinoflagellete polyketide synthesis as well as the role of protein phosphatases in cell growth.
Maitotoxin (MTX) is an extremely potent biotoxin produced by Gambierdiscus toxicus, a dinoflagellate species. Maitotoxin has been shown to be more than one hundred thousand times as potent as VX nerve agent. 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.
Cyclopiazonic acid (α-CPA), a mycotoxin and a fungal neurotoxin, is made by the molds Aspergillus and Penicillium. It is an indole-tetramic acid that serves as a toxin due to its ability to inhibit calcium-dependent ATPases found in the endoplasmic and sarcoplasmic reticulum. This inhibition disrupts the muscle contraction-relaxation cycle and the calcium gradient that is maintained for proper cellular activity in cells.
Prymnesium parvum is a species of haptophyte. The species is of concern because of its ability to produce the phycotoxin prymnesin. It is a flagellated alga that is normally found suspended in the water column. It was first identified in North America in 1985, but it is not known if it was introduced artificially or missed in previous surveys. Toxin production mainly kills fish and appears to have little effect on cattle or humans. This distinguishes it from a red tide, which is an algal bloom whose toxins lead to harmful effects in people. Although no harmful effects are known, it is recommended not to consume dead or dying fish exposed to a P. parvum bloom.
α-Bungarotoxin is one of the bungarotoxins, components of the venom of the elapid Taiwanese banded krait snake. It is a type of α-neurotoxin, a neurotoxic protein that is known to bind competitively and in a relatively irreversible manner to the nicotinic acetylcholine receptor found at the neuromuscular junction, causing paralysis, respiratory failure, and death in the victim. It has also been shown to play an antagonistic role in the binding of the α7 nicotinic acetylcholine receptor in the brain, and as such has numerous applications in neuroscience research.
Mycolactone is a polyketide-derived macrolide produced and secreted by a group of very closely related pathogenic mycobacteria species including M. ulcerans, M. liflandii, M. pseudoshottsii, and some strains of M. marinum. These mycobacteria are collectively referred to as mycolactone-producing mycobacteria or MPM.
Gambierdiscus toxicus is a species of photosynthetic unicellular eukaryote belonging to the Alveolata, part of the SAR supergroup. It is a dinoflagellate which can cause the foodborne illness ciguatera, and is known to produce several natural polyethers including ciguatoxin, maitotoxin, gambieric acid, and gambierol. The species was discovered attached to the surface of brown macroalgae.
Salinomycin is an antibacterial and coccidiostat ionophore therapeutic drug.
Lyngbyatoxin-a is a cyanotoxin produced by certain cyanobacteria species, most notably Moorea producens. It is produced as defense mechanism to ward off any would-be predators of the bacterium, being a potent blister agent as well as carcinogen. Low concentrations cause a common skin condition known as seaweed dermatitis.
Euglenophycin is an ichthyotoxic compound isolated from Euglena sanguinea, a protist of the genus Euglena. It exhibits anticancer and herbicidal activity in vitro.
Azaspiracids (AZA) are a group of polycyclic ether marine algal toxins produced by the small dinoflagellate Azadinium spinosum that can accumulate in shellfish and thereby cause illness in humans.
Dinotoxins are a group of toxins which are produced by flagellate, aquatic, unicellular protists called dinoflagellates. Dinotoxin was coined by Hardy and Wallace in 2012 as a general term for the variety of toxins produced by dinoflagellates. Dinoflagellates are an enormous group of marine life, with much diversity. With great diversity comes many different toxins, however, there are a few toxins that multiple species have in common.
Antillatoxin (ATX) is a potent lipopeptide neurotoxin produced by the marine cyanobacterium Lyngbya majuscula. ATX activates voltage-gated sodium channels, which can cause cell depolarisation, NMDA-receptor overactivity, excess calcium influx and neuronal necrosis.
Gambierol is a marine polycyclic ether toxin which is produced by the dinoflagellate Gambierdiscus toxicus. Gambierol is collected from the sea at the Rangiroa Peninsula in French Polynesia. The toxins are accumulated in fish through the food chain and can therefore cause human intoxication. The symptoms of the toxicity resemble those of ciguatoxins, which are extremely potent neurotoxins that bind to voltage-sensitive sodium channels and alter their function. These ciguatoxins cause ciguatera fish poisoning. Because of the resemblance, there is a possibility that gambierol is also responsible for ciguatera fish poisoning. Because the natural source of gambierol is limited, biological studies are hampered. Therefore, chemical synthesis is required.
Prymnesin-2 is an organic compound that is secreted by the haptophyte Prymnesium parvum. It belongs to the prymnesin family and has potent hemolytic and ichthyotoxic properties. In a purified form it appears as a pale yellow solid. P. parvum is responsible for red harmful algal blooms worldwide, causing massive fish killings. When these algal blooms occur, this compound poses a threat to the local fishing industry. This is especially true for brackish water, as the compound can reach critical concentrations more easily.
Prymnesin-B1 is a chemical with the molecular formula C
91H
132ClNO
34. It is a member of the prymnesins, a class of ladder-frame polyether phycotoxins made by the alga Prymnesium parvum. It is known to be toxic to fish. It is a so called "B-type" prymnesin, which differ in the number of backbone cycles when compared to A-type prymnesins like prymnesin-2.
Karlodinium veneficum is a species of dinoflagellates belonging to the family Kareniaceae. This species is predominantly inhabiting aquatic environments, particularly in temperate coastal regions.
Scaritoxin, a potent toxic substance, is a ciguatoxin with molecular formula C60H84O16. Scaritoxin is also referred to as ciguaotoxin 4A, CTX4A. Like other ciguatoxins, CTX4A is produced by dinoflagellate Gambierdiscus toxicus and isolated from poisonous fish.
