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Phallolysin
Phallolysin is a Protein found the ''Amanita phalloides'' species of the '' Amanita'' genus of mushrooms, the species commonly known as the death cap mushroom. The protein is toxic and causes Cytolysis in many cells found in animals, and is noted for its Hemolytic properties. It was one of the first toxins discovered in ''Amanita phalloides'' when the various toxins in the species where first being researched. The protein itself is observed to come in 3 variations, with observed differences in Isoelectric point. History The toxic properties of death cap mushrooms have been known for most of recorded history, with historical accounts implicating it in the deaths of emperors. Attempts to isolate the toxic compounds began in the late 19th century, with the cytolytic elements of ''A. phalloides'' being isolated in 1891. Physical properties Phallolysin has three variations, which differ in observed Isoelectric point. The variations have differences in the amino acids that make u ... [...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] |
Antamanide
Antamanide is a cyclic decapeptide isolated from a fungus, the death cap: ''Amanita phalloides''. It is being studied as a potential anti-toxin against the effects of phalloidin and for its potential for treating edema. It contains 1 valine residue, 4 proline residues, 1 alanine residue, and 4 phenylalanine residues with a structure of c(Val-Pro-Pro-Ala-Phe-Phe-Pro-Pro-Phe-Phe). It was isolated by determining the source of the anti-phalloidin activity from a lipophillic extraction from the organism. It has been shown that antamanide can react to form alkali metal ion complexes. These include complexes with sodium and calcium ions. When these complexes are formed, the cyclopeptide structure undergoes a conformational change. Biochemical Properties of Antamanide Anantamide has been shown to make many different types of biochemical activity. Effect of Altering The Peptide Structure on the Anti-Phalloidin Activity It has been shown that altering any of the proline residues reduces th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, responding to stimuli, providing structure to cells and organisms, and transporting molecules from one location to another. Proteins differ from one another primarily in their sequence of amino acids, which is dictated by the nucleotide sequence of their genes, and which usually results in protein folding into a specific 3D structure that determines its activity. A linear chain of amino acid residues is called a polypeptide. A protein contains at least one long polypeptide. Short polypeptides, containing less than 20–30 residues, are rarely considered to be proteins and are commonly called peptides. The individual amino acid residues are bonded together by peptide bonds and adjacent amino acid residues. The sequence of amino acid residue ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amanita
The genus ''Amanita'' contains about 600 species of agarics, including some of the most toxic known mushrooms found worldwide, as well as some well-regarded edible species. This genus is responsible for approximately 95% of the fatalities resulting from mushroom poisoning, with the death cap accounting for about 50% on its own. The most potent toxin present in these mushrooms is α-Amanitin. The genus also contains many edible mushrooms, but mycologists discourage mushroom hunters, other than experts, from selecting any of these for human consumption. Nonetheless, in some cultures, the larger local edible species of ''Amanita'' are mainstays of the markets in the local growing season. Samples of this are ''Amanita zambiana'' and other fleshy species in central Africa, ''Amanita basii, A. basii'' and similar species in Mexico, ''Amanita caesarea, A. caesarea'' and the "Blusher" ''Amanita rubescens'' in Europe, and ''Amanita chepangiana, A. chepangiana'' in South-East Asia. Other s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cytolysis
Cytolysis, or osmotic lysis, occurs when a cell bursts due to an osmotic imbalance that has caused excess water to diffuse into the cell. Water can enter the cell by diffusion through the cell membrane or through selective membrane channels called aquaporins, which greatly facilitate the flow of water. It occurs in a hypotonic environment, where water moves into the cell by osmosis and causes its volume to increase to the point where the volume exceeds the membrane's capacity and the cell bursts. The presence of a cell wall prevents the membrane from bursting, so cytolysis only occurs in animal and protozoa cells which do not have cell walls. The reverse process is plasmolysis. In bacteria Osmotic lysis would be expected to occur when bacterial cells are treated with a hypotonic solution with added lysozyme, which destroys the bacteria's cell walls. Prevention Different cells and organisms have adapted different ways of preventing cytolysis from occurring. For example, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hemolysis
Hemolysis or haemolysis (), also known by several other names, is the rupturing (lysis) of red blood cells (erythrocytes) and the release of their contents (cytoplasm) into surrounding fluid (e.g. blood plasma). Hemolysis may occur in vivo or in vitro. One cause of hemolysis is the action of hemolysins, toxins that are produced by certain pathogenic bacteria or fungi. Another cause is intense physical exercise. Hemolysins damage the red blood cell's cytoplasmic membrane, causing lysis and eventually cell death. Etymology From hemo- + -lysis, from , "blood") + , "loosening"). Inside the body Hemolysis inside the body can be caused by a large number of medical conditions, including some parasites (''e.g.'', ''Plasmodium''), some autoimmune disorders (''e.g.'', autoimmune haemolytic anaemia, drug-induced hemolytic anemia, atypical hemolytic uremic syndrome (aHUS)), some genetic disorders (''e.g.'', Sickle-cell disease or G6PD deficiency), or blood with too low a solute conc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isoelectric Point
The isoelectric point (pI, pH(I), IEP), is the pH at which a molecule carries no net electrical charge or is electrically neutral in the statistical mean. The standard nomenclature to represent the isoelectric point is pH(I). However, pI is also used. For brevity, this article uses pI. The net charge on the molecule is affected by pH of its surrounding environment and can become more positively or negatively charged due to the gain or loss, respectively, of protons (H+). Surfaces naturally charge to form a double layer. In the common case when the surface charge-determining ions are H+/HO−, the net surface charge is affected by the pH of the liquid in which the solid is submerged. The pI value can affect the solubility of a molecule at a given pH. Such molecules have minimum solubility in water or salt solutions at the pH that corresponds to their pI and often precipitate out of solution. Biological amphoteric molecules such as proteins contain both acidic and basic function ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein Structure
Protein structure is the three-dimensional arrangement of atoms in an amino acid-chain molecule. Proteins are polymers specifically polypeptides formed from sequences of amino acids, the monomers of the polymer. A single amino acid monomer may also be called a ''residue'' indicating a repeating unit of a polymer. Proteins form by amino acids undergoing condensation reactions, in which the amino acids lose one water molecule per reaction in order to attach to one another with a peptide bond. By convention, a chain under 30 amino acids is often identified as a peptide, rather than a protein. To be able to perform their biological function, proteins fold into one or more specific spatial conformations driven by a number of non-covalent interactions such as hydrogen bonding, ionic interactions, Van der Waals forces, and hydrophobic packing. To understand the functions of proteins at a molecular level, it is often necessary to determine their three-dimensional structure. This is t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dalton (unit)
The dalton or unified atomic mass unit (symbols: Da or u) is a non-SI unit of mass widely used in physics and chemistry. It is defined as of the mass of an unbound neutral atom of carbon-12 in its nuclear and electronic ground state and at rest. The atomic mass constant, denoted ''m''u, is defined identically, giving . This unit is commonly used in physics and chemistry to express the mass of atomic-scale objects, such as atoms, molecules, and elementary particles, both for discrete instances and multiple types of ensemble averages. For example, an atom of helium-4 has a mass of . This is an intrinsic property of the isotope and all helium-4 atoms have the same mass. Acetylsalicylic acid (aspirin), , has an average mass of approximately . However, there are no acetylsalicylic acid molecules with this mass. The two most common masses of individual acetylsalicylic acid molecules are , having the most common isotopes, and , in which one carbon is carbon-13. The molecular mass ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mammal
Mammals () are a group of vertebrate animals constituting the class Mammalia (), characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fur or hair, and three middle ear bones. These characteristics distinguish them from reptiles (including birds) from which they diverged in the Carboniferous, over 300 million years ago. Around 6,400 extant species of mammals have been described divided into 29 orders. The largest orders, in terms of number of species, are the rodents, bats, and Eulipotyphla (hedgehogs, moles, shrews, and others). The next three are the Primates (including humans, apes, monkeys, and others), the Artiodactyla ( cetaceans and even-toed ungulates), and the Carnivora (cats, dogs, seals, and others). In terms of cladistics, which reflects evolutionary history, mammals are the only living members of the Synapsida (synapsids); this clade, together with Saur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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] |
