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Phallotoxin
The phallotoxins consist of at least seven compounds, all of which are bicyclic heptapeptides (seven amino acids), isolated from the death cap mushroom ''(Amanita phalloides)''. They differ from the closely related amatoxins by being one residue smaller, both in the final product and the precursor protein. Phalloidin had been isolated in 1937 by Feodor Felix Konrad Lynen, Feodor Lynen, Heinrich Wieland's student and son-in-law, and Ulrich Wieland of the University of Munich. The remaining six are prophalloin, phalloin, phallisin, phallacidin, phallacin and phallisacin. Though highly toxic to liver cells, phallotoxins have since been found to have little contribution to the death cap's toxicity because they are not absorbed through the gut. Reports of phalloidin in the edible (and sought after) Blusher (''Amanita rubescens'') have not been confirmed by later researchersHallen HE, Adams GC, Eicker A (2002) Amatoxins and phallotoxins in indigenous and introduced South African Amanita sp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amatoxin
Amatoxin is the collective name of a subgroup of at least nine related toxic compounds found in three genera of poisonous mushrooms (''Amanita'', ''Galerina'' and ''Lepiota'') and one species (Conocybe filaris) of the genus ''Conocybe''. Amatoxins are lethal in even small doses, as little as half a mushroom, including the immature 'egg' form which appears quite different from the fully-grown mushroom. Although laboratory analysis has found that the spores contain as little as 3% the toxin concentration of the main mushroom body, anecdotes have been repeated in field guides that claim foragers have fallen ill from spores alone after collecting but then discarding toxic Amanitas, unknowingly leaving their spore dust on the remaining harvest. Unlike many ingested poisons, they cannot be destroyed by heat without destroying the mushrooms beyond edibility first, so cooking the poisonous mushrooms does not diminish their lethality. Structure The compounds have a similar structure, tha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phalloidin
Phalloidin belongs to a class of toxins called phallotoxins, which are found in the death cap mushroom ''(Amanita phalloides)''. It is a rigid bicyclic heptapeptide that is lethal after a few days when injected into the bloodstream. The major symptom of phalloidin poisoning is acute hunger due to the destruction of liver cells. It functions by binding and stabilizing filamentous actin (F-actin) and effectively prevents the depolymerization of actin fibers. Due to its tight and selective binding to F-actin, derivatives of phalloidin containing fluorescent tags are used widely in microscopy to visualize F-actin in biomedical research. Discovery and background Phalloidin was one of the first cyclic peptides to be discovered. It was isolated from the death cap mushroom and crystallized by Feodor Lynen and Ulrich WielandG. Semenza, E.C. Slater, R. JaenickeSelected Topics in the History of Biochemistry. Personal Recollections- Google books in 1937. Its structure is unusual in that it co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amanita Phalloides
''Amanita phalloides'' (), commonly known as the death cap, is a deadly poisonous basidiomycete fungus, one of many in the genus ''Amanita''. Widely distributed across Europe, but now sprouting in other parts of the world, ''A. phalloides'' forms ectomycorrhizas with various broadleaved trees. In some cases, the death cap has been introduced to new regions with the cultivation of non-native species of oak, chestnut, and pine. The large fruiting bodies (mushrooms) appear in summer and autumn; the caps are generally greenish in colour with a white stipe and gills. The cap colour is variable, including white forms, and is thus not a reliable identifier. These toxic mushrooms resemble several edible species (most notably Caesar's mushroom and the straw mushroom) commonly consumed by humans, increasing the risk of accidental poisoning. Amatoxins, the class of toxins found in these mushrooms, are thermostable: they resist changes due to heat, so their toxic effects are not red ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heptapeptide
Peptides (, ) are short chains of amino acids linked by peptide bonds. Long chains of amino acids are called proteins. Chains of fewer than twenty amino acids are called oligopeptides, and include dipeptides, tripeptides, and tetrapeptides. A polypeptide is a longer, continuous, unbranched peptide chain. Hence, peptides fall under the broad chemical classes of biological polymers and oligomers, alongside nucleic acids, oligosaccharides, polysaccharides, and others. A polypeptide that contains more than approximately 50 amino acids is known as a protein. Proteins consist of one or more polypeptides arranged in a biologically functional way, often bound to ligands such as coenzymes and cofactors, or to another protein or other macromolecule such as DNA or RNA, or to complex macromolecular assemblies. Amino acids that have been incorporated into peptides are termed residues. A water molecule is released during formation of each amide bond.. All peptides except cyclic peptides ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mycotoxins Found In Basidiomycota
A mycotoxin (from the Greek μύκης , "fungus" and τοξίνη , "toxin") is a toxic secondary metabolite produced by organisms of kingdom Fungi and is capable of causing disease and death in both humans and other animals. The term 'mycotoxin' is usually reserved for the toxic chemical products produced by fungi that readily colonize crops. Examples of mycotoxins causing human and animal illness include aflatoxin, citrinin, fumonisins, ochratoxin A, patulin, trichothecenes, zearalenone, and ergot alkaloids such as ergotamine. One mold species may produce many different mycotoxins, and several species may produce the same mycotoxin. Production Most fungi are aerobic (use oxygen) and are found almost everywhere in extremely small quantities due to the diminute size of their spores. They consume organic matter wherever humidity and temperature are sufficient. Where conditions are right, fungi proliferate into colonies and mycotoxin levels become high. The reason for the producti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scientific American
''Scientific American'', informally abbreviated ''SciAm'' or sometimes ''SA'', is an American popular science magazine. Many famous scientists, including Albert Einstein and Nikola Tesla, have contributed articles to it. In print since 1845, it is the oldest continuously published magazine in the United States. ''Scientific American'' is owned by Springer Nature, which in turn is a subsidiary of Holtzbrinck Publishing Group. History ''Scientific American'' was founded by inventor and publisher Rufus Porter (painter), Rufus Porter in 1845 as a four-page weekly newspaper. The first issue of the large format newspaper was released August 28, 1845. Throughout its early years, much emphasis was placed on reports of what was going on at the United States Patent and Trademark Office, U.S. Patent Office. It also reported on a broad range of inventions including perpetual motion machines, an 1860 device for buoying vessels by Abraham Lincoln, and the universal joint which now can be found ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blusher
The blusher is the common name for several closely related species of the genus ''Amanita''. ''A. rubescens'' or the blushing amanita, is found in Europe and eastern North America, and ''A. novinupta'', also known as the new bride blushing amanita, is found in western North America. Both their scientific and common names are derived from the propensity of their flesh to turn pink on bruising, or cutting. The mushroom is edible and tasty, sought for in several European countries. It is readily recognizable by its pinkish color on the bottom of the stem. It is avoided by novice mushroomers as without knowledge it can be confused with deadly poisonous species. Description The European blusher has a reddish-brown convex Pileus (mycology), pileus (cap), that is 5–15 cm across, and strewn with small white-to-mahogany warts. It is sometimes covered with an ochre-yellow flush which can be washed by the rain. The flesh of the mushroom is white, becoming pink when bruised or expos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
