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Toxalbumin
Toxalbumins are toxic plant proteins that disable ribosomes and thereby inhibit protein synthesis, producing severe cytotoxic effects in multiple organ systems. They are dimers held together by a disulfide bond and comprise a lectin (carbohydrate-binding protein) part which binds to the cell membrane and enables the toxin part to gain access to the cell contents. Toxalbumins are similar in structure to AB toxins found in cholera, tetanus, diphtheria, botulinum and others; and their physiological and toxic properties are similar to those of viperine snake venom. Toxalbumins were first described in about 1890 by Ludwig Brieger (1849–1919) and Sigmund Fraenkel (1868–1939), associates of the organic chemist Eugen Baumann. Brieger first used the term toxin. Toxalbumins notably are present in the plant families Leguminosae and Euphorbiaceae, occurring for instance in ''Robinia pseudoacacia'', ''Abrus precatorius'', ''Jatropha curcas'', '' Croton gratissimus'' and ''Ricinus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AB Toxin
The AB toxins are two-component protein complexes secreted by a number of pathogenicity, pathogenic bacteria, though there is a pore-forming AB toxin found the eggs of a snail. They can be classified as Exotoxin#Type III: intracellular, Type III toxins because they interfere with internal cell function. They are named AB toxins due to their components: the "A" component is usually the "active" portion, and the "B" component is usually the "binding" portion. The "A" subunit possesses enzyme activity, and is transferred to the host cell (biology), cell following a conformational change in the membrane-bound transport "B" subunit. These proteins consist of two independent polypeptides, which correspond to the A/B subunit Moiety (chemistry), moieties. The enzyme component (A) enters the cell (biology), cell through endosomes produced by the oligomeric binding/translocation protein (B), and prevents actin polymerisation through ADP-ribosylation of monomeric G-actin. Examples of the "A" ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ricinus Communis
''Ricinus communis'', the castor bean or castor oil plant, is a species of perennial flowering plant in the spurge family, Euphorbiaceae. It is the sole species in the monotypic genus, ''Ricinus'', and subtribe, Ricininae. The evolution of castor and its relation to other species are currently being studied using modern genetic tools. It reproduces with a mixed pollination system which favors selfing by geitonogamy but at the same time can be an out-crosser by anemophily (wind pollination) or entomophily (insect pollination). Its seed is the castor bean, which, despite its name, is not a bean (that is, the seed of many Fabaceae). Castor is indigenous to the southeastern Mediterranean Basin, Eastern Africa, and India, but is widespread throughout tropical regions (and widely grown elsewhere as an ornamental plant). Castor seed is the source of castor oil, which has a wide variety of uses. The seeds contain between 40% and 60% oil that is rich in triglycerides, mainly ricinolei ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lectin
Lectins are carbohydrate-binding proteins that are highly specific for sugar groups that are part of other molecules, so cause agglutination of particular cells or precipitation of glycoconjugates and polysaccharides. Lectins have a role in recognition at the cellular and molecular level and play numerous roles in biological recognition phenomena involving cells, carbohydrates, and proteins. Lectins also mediate attachment and binding of bacteria, viruses, and fungi to their intended targets. Lectins are ubiquitous in nature and are found in many foods. Some foods, such as beans and grains, need to be cooked, fermented or sprouted to reduce lectin content. Some lectins are beneficial, such as CLEC11A, which promotes bone growth, while others may be powerful toxins such as ricin. Lectins may be disabled by specific mono- and oligosaccharides, which bind to ingested lectins from grains, legumes, nightshade plants, and dairy; binding can prevent their attachment to the carbohy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toxin
A toxin is a naturally occurring organic poison produced by metabolic activities of living cells or organisms. Toxins occur especially as a protein or conjugated protein. The term toxin was first used by organic chemist Ludwig Brieger (1849–1919) and is derived from the word toxic. Toxins can be small molecules, peptides, or proteins that are capable of causing disease on contact with or absorption by body tissues interacting with biological macromolecules such as enzymes or cellular receptors. Toxins vary greatly in their toxicity, ranging from usually minor (such as a bee sting) to potentially fatal even at extremely low doses (such as botulinum toxin). Toxins are largely secondary metabolites, which are organic compounds that are not directly involved in an organism's growth, development, or reproduction, instead often aiding it in matters of defense. Terminology Toxins are often distinguished from other chemical agents strictly based on their biological origin. Le ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Euphorbiaceae
Euphorbiaceae, the spurge family, is a large family of flowering plants. In English, they are also commonly called euphorbias, which is also the name of a genus in the family. Most spurges, such as ''Euphorbia paralias'', are herbs, but some, especially in the tropics, are shrubs or trees, such as ''Hevea brasiliensis''. Some, such as ''Euphorbia canariensis'', are succulent and resemble cacti because of convergent evolution. This family has a cosmopolitan global distribution. The greatest diversity of species is in the tropics, however, the Euphorbiaceae also have many species in nontropical areas of all continents except Antarctica. Description The leaves are alternate, seldom opposite, with stipules. They are mainly simple, but where compound, are always palmate, never pinnate. Stipules may be reduced to hairs, glands, or spines, or in succulent species are sometimes absent. The plants can be monoecious or dioecious. The radially symmetrical flowers are unisexual, w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Robinia Pseudoacacia
''Robinia pseudoacacia'', commonly known in its native territory as black locust, is a medium-sized hardwood deciduous tree, belonging to the tribe Robinieae of the legume family Fabaceae. It is endemic to a few small areas of the United States, but it has been widely planted and naturalized elsewhere in temperate North America, Europe, Southern Africa and Asia and is considered an invasive species in some areas. Another common name is false acacia, a literal translation of the specific name (''pseudo'' reek ''ψευδο-''meaning fake or false and ''acacia'' referring to the genus of plants with the same name). Description Black locust reaches a typical height of with a diameter of . It is a very upright tree with a straight trunk and narrow crown that grows scraggly with age. The dark blue-green compound leaves with a contrasting lighter underside give this tree a beautiful appearance in the wind and contribute to its grace. Black locust is a shade-intolerant species and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abrus Precatorius
''Abrus precatorius'', commonly known as jequirity bean or rosary pea, is a herbaceous flowering plant in the bean family Fabaceae. It is a slender, perennial climber with long, pinnate-leafleted leaves that twines around trees, shrubs, and hedges. The plant is best known for its seeds, which are used as beads and in percussion instruments, and which are toxic because of the presence of abrin. Ingestion of a single seed, well chewed, can be fatal to both adults and children. The plant is native to Asia and Australia. It has a tendency to become weedy and invasive where it has been introduced. Names ''Abrus precatorius'' is commonly known as jequirity, Crab's eye, or rosary pea, paternoster pea, love pea, precatory pea or bean, prayer bead, John Crow Bead, coral bead, red-bead vine, country licorice, Indian licorice, wild licorice, Jamaica wild licorice, gundumani/kundumani (in India/Tamil), Akar Saga, coondrimany, gidee gidee, Jumbie bead,Mendes (1986), p. 79. ratti / rettee / r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jatropha Curcas
''Jatropha curcas'' is a species of flowering plant in the spurge family, Euphorbiaceae, that is native to the American tropics, most likely Mexico and Central America. It is originally native to the tropical areas of the Americas from Mexico to Argentina, and has been spread throughout the world in tropical and subtropical regions around the world, becoming naturalized or invasive in many areas. The specific epithet, ''"curcas"'', was first used by Portuguese doc Garcia de Orta more than 400 years ago. Common names in English include physic nut, Barbados nut, poison nut, bubble bush or purging nut. In parts of Africa and areas in Asia such as India it is often known as "castor oil plant" or "hedge castor oil plant", but it is not the same as the usual castor oil plant, ''Ricinus communis'' (they are in the same family but different subfamilies). ''J. curcas'' is a semi-evergreen shrub or small tree, reaching a height of or more. It is resistant to a high degree of aridity, al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Croton Gratissimus
''Croton gratissimus'' (commonly known as lavender croton or lavender fever berry), is a tropical African shrub or small tree with corky bark, growing to 8 m and belonging to the family of Euphorbiaceae or spurges. Young twigs are slender and angular and covered in silver and rust-coloured scales. The species occurs in Ethiopia, South Sudan, Sudan, Kenya, Uganda, Ivory Coast, Burkina Faso, the Gambia, Ghana, Guinea, Nigeria, Angola, Malawi, Mozambique, Zambia, Zimbabwe and the northern parts of South Africa. It is often found in rocky terrain. Description The crushed, slender-petioled leaves are pleasingly and distinctively fragrant with an aromatic oil reminiscent of sweet flag. The leaves are strikingly silver on the under surface and dotted with brown glands. The inflorescence is a yellow-flowered raceme up to 10 cm long and borne terminally. Rust-coloured flower buds, which are present throughout winter, open after the first rains. The fruit is a 3-lobed capsule, ab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Illustration Ricinus Communis0
An illustration is a decoration, interpretation or visual explanation of a text, concept or process, designed for integration in print and digital published media, such as posters, flyers, magazines, books, teaching materials, animations, video games and films. An illustration is typically created by an illustrator. Digital illustrations are often used to make websites and apps more user-friendly, such as the use of emojis to accompany digital type. llustration also means providing an example; either in writing or in picture form. The origin of the word "illustration" is late Middle English (in the sense ‘illumination; spiritual or intellectual enlightenment’): via Old French from Latin ''illustratio''(n-), from the verb ''illustrare''. Illustration styles Contemporary illustration uses a wide range of styles and techniques, including drawing, painting, printmaking, collage, montage, digital design, multimedia, 3D modelling. Depending on the purpose, illustration ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abrin
Abrin is an extremely toxic toxalbumin found in the seeds of the rosary pea (or jequirity pea), ''Abrus precatorius''. It has a median lethal dose of 0.7 micrograms per kilogram of body mass when given to mice intravenously (approximately 31.4 times more toxic than ricin, being 22 micrograms per kilogram). The median toxic dose for humans ranges from 10 to 1000 micrograms per kilogram when ingested and is 3.3 micrograms per kilogram when inhaled. Abrin is a ribosome inhibiting protein like ricin, a toxin which can be found in the seeds of the castor oil plant, and pulchellin, a toxin which can be found in the seeds of '' Abrus pulchellus''. Abrin is classed as a "select agent" under U.S. law. Occurrence Abrin is only formed in nature by the rosary pea. The brightly coloured seeds of this plant contain about 0.08% of abrin. The toxin is found within the seeds and its release is prevented by the seed coat. If the seed coat is injured or destroyed (by chewing, for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ricin
Ricin ( ) is a lectin (a carbohydrate-binding protein) and a highly potent toxin produced in the seeds of the castor oil plant, ''Ricinus communis''. The median lethal dose (LD50) of ricin for mice is around 22 micrograms per kilogram of body weight via intraperitoneal injection. Oral exposure to ricin is far less toxic. An estimated lethal oral dose in humans is approximately 1 milligram per kilogram of body weight. Ricin was first described by Peter Hermann Stillmark, the founder of lectinology. Biochemistry Ricin is classified as a type 2 ribosome-inactivating protein (RIP). Whereas type 1 RIPs are composed of a single protein chain that possesses catalytic activity, type 2 RIPs, also known as holotoxins, are composed of two different protein chains that form a heterodimeric complex. Type 2 RIPs consist of an A chain that is functionally equivalent to a type 1 RIP, covalently connected by a single disulfide bond to a B chain that is catalytically inactive, but serves to m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
