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Opisthacanthus Capensis
''Opisthacanthus capensis'' is a Cape Province and Zimbabwean species of scorpion with robust chelae, dark brown to black in colour, turning green when under cover for some time. ''Opisthacanthus'' scorpions are arboreal and ground-dwelling, and found mainly in moist habitats in dense vegetation, pine plantations and forests, and hiding under bark and rocks. Its venom contains powerful neurotoxins and cytotoxins, including mucopolysaccharides, hyaluronidases, phospholipases, serotonins, histamines, enzyme inhibitors, and proteins such as neurotoxic peptides. The venom from ''O. capensis'' is largely composed of melittin which stimulates the release of the enzyme phospholipase A2 causing inflammation and pain. Phospholipase A2 cleaves the SN-2 acyl chain, releasing arachidonic acid. This species features in the diets of the bat-eared fox ''Otocyon megalotis'' (Canidae), the yellow mongoose ''Cynictis penicillata'', the small grey mongoose ''Galerella pulverulenta'', and the water ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Johann Friedrich Wilhelm Herbst
Johann Friedrich Wilhelm Herbst (1 November 1743 – 5 November 1807) was a German naturalist and entomologist from Petershagen, Minden-Ravensberg. He served as a chaplain in the Prussian army. His marriage in Berlin, 1770, with Euphrosyne Luise Sophie (1742–1805), daughter of the Prussian ''Hofrat'' Libert Waldschmidt seems to have been childless. He was the joint editor, with , of ''Naturgeschichte der in- und ausländischen Insekten'' (1785–1806, 10 volumes), which was one of the first attempts at a complete survey of the order [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Serotonin
Serotonin () or 5-hydroxytryptamine (5-HT) is a monoamine neurotransmitter. Its biological function is complex and multifaceted, modulating mood, cognition, reward, learning, memory, and numerous physiological processes such as vomiting and vasoconstriction. Approximately 90% of the serotonin that the body produces is in the intestinal tract. Biochemically, the indoleamine molecule derives from the amino acid tryptophan, via the (rate-limiting) hydroxylation of the 5 position on the ring (forming the intermediate 5-hydroxytryptophan), and then decarboxylation to produce serotonin. Serotonin is primarily found in the enteric nervous system located in the gastrointestinal tract (GI tract). However, it is also produced in the central nervous system (CNS), specifically in the raphe nuclei located in the brainstem, Merkel cells located in the skin, pulmonary neuroendocrine cells and taste receptor cells in the tongue. Additionally, serotonin is stored in blood platelets and is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atilax Paludinosus
The marsh mongoose (''Atilax paludinosus''), also known as the water mongoose or the vansire, is a medium-sized mongoose native to sub-Saharan Africa that inhabits foremost freshwater wetlands. It has been listed as Least Concern on the IUCN Red List since 2008. Taxonomy The generic name ''Atilax'' was introduced in 1826 by Frédéric Cuvier. In 1829, Georges Cuvier referred to a mongoose in the marshes of the Cape Province using the scientific name ''Herpestes paludinosus''. It is the only extant member of the genus ''Atilax'', although an extinct ancestral species from the Early Pleistocene known as '' Atilax mesotes'' was also a member of the genus. Characteristics The marsh mongoose's fur is dark reddish brown to black with white and fawn coloured guard hairs. The hair behind the neck and in front of the back is short, but longer on the hind legs and on the tail. Its muzzle is short with a fawn coloured mouth, short whiskers and a naked rhinarium. It has teeth. Its sh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galerella Pulverulenta
The Cape grey mongoose (''Herpestes pulverulentus''), also called the small grey mongoose, is a small mammal native to South Africa, Lesotho and southern Namibia. Appearance It is a small species (55–69 cm long, weight range 0.5 – 1.0 kg). It is a dark grey colour with a darker tip of the tail. The legs are a darker grey than the rest of the body. It has a typical elongated mongoose body-shape. The ears are small and rounded and are situated on the sides of the head. The tail is long and bushy. The teeth show adaptations for both cutting and crushing. Diet and behaviour The Cape grey mongoose feeds mostly on insects and small rodents, but will also eat birds, small reptiles, amphibians, other invertebrates, and fruit. They have been known to eat carrion and garbage as well. It is predominantly insectivorous but also carnivorous. Insects and other arthropoda such as spiders are caught on the ground and then held down with the forefeet and eaten. Larger ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cynictis Penicillata
The yellow mongoose (''Cynictis penicillata''), sometimes referred to as the red meerkat, is a member of the mongoose family. It averages about in weight and about in length. It lives in open country, semi-desert scrubland and grasslands in Angola, Botswana, South Africa, Namibia, and Zimbabwe. It is the only species in the genus ''Cynictis''. Taxonomy ''Herpestes penicillatus'' was the scientific name proposed by Georges Cuvier in 1829 for a mongoose specimen from the Cape. The generic name ''Cynictis'' was proposed by William Ogilby in 1833 for a specimen collected in Kaffraria. ''Cynictis penicillata'' is the only member of the genus, but as many as twelve subspecies of yellow mongoose have been described. Characteristics In general, the yellow mongoose has lighter highlights on the underbelly and chin, a bushy tail, and a complete lack of sexual dimorphism. Southern yellow mongooses are larger, have yellow or reddish fur, longer fur, and a longer tail with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Otocyon Megalotis
The bat-eared fox (''Otocyon megalotis'') is a species of fox found on the African savanna. It is the only extant species of the genus ''Otocyon'' and considered a basal canid species. Fossil records indicate this canid first appeared during the middle Pleistocene. It is named for its large ears, which have a role in thermoregulation. The bat referred to in its colloquial name is possibly the Egyptian slit-faced bat (''Nycteris thebaica''), which is abundant in the region and has very large ears. Although not commonly used, other vernacular names include big-eared fox, black-eared fox, long-eared fox, Delalande's fox, cape fox, and motlosi. Systematics and evolution The bat-eared fox is the only living species of the genus ''Otocyon''. Its scientific name, given by Anselme Gaëtan Desmarest, was initially ''Canis megalotis'' (due to its close resemblance to jackals), and later changed by Salomon Müller which placed it in its own genus, ''Otocyon''; its huge ears and diffe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arachidonic Acid
Arachidonic acid (AA, sometimes ARA) is a polyunsaturated omega-6 fatty acid 20:4(ω-6), or 20:4(5,8,11,14). It is structurally related to the saturated arachidic acid found in cupuaçu butter. Its name derives from the New Latin word ''arachis'' (peanut), but peanut oil does not contain any arachidonic acid. Chemistry In chemical structure, arachidonic acid is a carboxylic acid with a 20-carbon chain and four ''cis''-double bonds; the first double bond is located at the sixth carbon from the omega end. Some chemistry sources define 'arachidonic acid' to designate any of the eicosatetraenoic acids. However, almost all writings in biology, medicine, and nutrition limit the term to ''all cis''-5,8,11,14-eicosatetraenoic acid. Biology Arachidonic acid is a polyunsaturated fatty acid present in the phospholipids (especially phosphatidylethanolamine, phosphatidylcholine, and phosphatidylinositides) of membranes of the body's cells, and is abundant in the brain, muscles, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acyl Chain
In chemistry, an acyl group is a moiety derived by the removal of one or more hydroxyl groups from an oxoacid, including inorganic acids. It contains a double-bonded oxygen atom and an alkyl group (). In organic chemistry, the acyl group (IUPAC name: alkanoyl) is usually derived from a carboxylic acid, in which case it has the formula , where R represents an alkyl group that is linked to the carbon atom of the group by a single bond. Although the term is almost always applied to organic compounds, acyl groups can in principle be derived from other types of acids such as sulfonic acids and phosphonic acids. In the most common arrangement, acyl groups are attached to a larger molecular fragment, in which case the carbon and oxygen atoms are linked by a double bond. Compounds Well-known acyl compounds are the acyl chlorides, such as acetyl chloride (CH3COCl) and benzoyl chloride (C6H5COCl). These compounds, which are treated as sources of acylium cations, are good reagents for at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phospholipase A2
The enzyme phospholipase A2 (EC 3.1.1.4, PLA2, systematic name phosphatidylcholine 2-acylhydrolase) catalyse the cleavage of fatty acids in position 2 of phospholipids, hydrolyzing the bond between the second fatty acid “tail” and the glycerol molecule: :phosphatidylcholine + H2O = 1-acylglycerophosphocholine + a carboxylate This particular phospholipase specifically recognizes the ''sn''2 acyl bond of phospholipids and catalytically hydrolyzes the bond, releasing arachidonic acid and lysophosphatidic acid. Upon downstream modification by cyclooxygenases or lipoxygenases, arachidonic acid is modified into active compounds called eicosanoids. Eicosanoids include prostaglandins and leukotrienes, which are categorized as anti-inflammatory and inflammatory mediators. PLA2 enzymes are commonly found in mammalian tissues as well as arachnid, insect, and snake venom. Venom from bees is largely composed of melittin, which is a stimulant of PLA2. Due to the increased presenc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Melittin
Melittin is the main component (40–60% of the dry weight) and the major pain producing substance of honeybee (''Apis mellifera'') venom. Melittin is a basic peptide consisting of 26 amino acids. Function The principal function of melittin as a component of bee venom is to cause pain and destruction of tissue of intruders that threaten a beehive. However, in honey bees, melittin is not only expressed in the venom gland, but also in other tissues when infected with pathogens. The two venom molecules, melittin and secapin, that are over-expressed in honey bees infected with various pathogens, possibly indicate a role for melittin in the immune response of bees to infectious diseases. Structure Melittin is a small peptide with no disulfide bridge; the ''N''-terminal part of the molecule is predominantly hydrophobic and the ''C''-terminal part is hydrophilic and strongly basic. In water, it forms a tetramer but it also can spontaneously integrate itself into cell membrane ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Histamine
Histamine is an organic nitrogenous compound involved in local immune responses, as well as regulating physiological functions in the gut and acting as a neurotransmitter for the brain, spinal cord, and uterus. Since histamine was discovered in 1910, it has been considered a local hormone (autocoid) because it lacks the classic endocrine glands to secrete it; however, in recent years, histamine has been recognized as a central neurotransmitter. Histamine is involved in the inflammatory response and has a central role as a mediator of itching. As part of an immune response to foreign pathogens, histamine is produced by basophils and by mast cells found in nearby connective tissues. Histamine increases the permeability of the capillaries to white blood cells and some proteins, to allow them to engage pathogens in the infected tissues. It consists of an imidazole ring attached to an ethylamine chain; under physiological conditions, the amino group of the side-chain is protonate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phospholipase
A phospholipase is an enzyme that hydrolyzes phospholipids into fatty acids and other lipophilic substances. Acids trigger the release of bound calcium from cellular stores and the consequent increase in free cytosolic Ca2+, an essential step in calcium signaling to regulate intracellular processes. There are four major classes, termed A, B, C, and D, which are distinguished by the type of reaction which they catalyze: *Phospholipase A **Phospholipase A1 – cleaves the ''sn''-1 acyl chain (where ''sn'' refers to stereospecific numbering). **Phospholipase A2 – cleaves the ''sn''-2 acyl chain, releasing arachidonic acid. * Phospholipase B – cleaves both ''sn''-1 and ''sn''-2 acyl chains; this enzyme is also known as a lysophospholipase. *Phospholipase C – cleaves before the phosphate, releasing diacylglycerol and a phosphate-containing head group. PLCs play a central role in signal transduction, releasing the second messenger inositol triphosphate. * Phospholipase D ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
