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An oligosaccharide is a saccharide polymer containing a small number of monosaccharides. Oligosaccharides can have many functions including cell recognition and cell adhesion.
Gyromitrin is a toxin and carcinogen present in several members of the fungal genus Gyromitra, like G. esculenta. Its formula is CH3CH=N−N(CH3)CHO. It is unstable and is easily hydrolyzed to the toxic compound monomethylhydrazine CH3NHNH2. Monomethylhydrazine acts on the central nervous system and interferes with the normal use and function of vitamin B6. Poisoning results in nausea, stomach cramps, and diarrhea, while severe poisoning can result in convulsions, jaundice, or even coma or death. Exposure to monomethylhydrazine has been shown to be carcinogenic in small mammals.
The Boletaceae are a family of mushroom-forming fungi, primarily characterised by small pores on the spore-bearing hymenial surface, instead of gills as are found in most agarics. Nearly as widely distributed as the agarics, the family is renowned for hosting some prime edible species highly sought after by mushroom hunters worldwide, such as the cep or king bolete . A number of rare or threatened species are also present in the family, that have become the focus of increasing conservation concerns. As a whole, the typical members of the family are commonly known as boletes.
Concanavalin A (ConA) is a lectin originally extracted from the jack-bean. It is a member of the legume lectin family. It binds specifically to certain structures found in various sugars, glycoproteins, and glycolipids, mainly internal and nonreducing terminal α-D-mannosyl and α-D-glucosyl groups. Its physiological function in plants, however, is still unknown. ConA is a plant mitogen, and is known for its ability to stimulate mouse T-cell subsets giving rise to four functionally distinct T cell populations, including precursors to regulatory T cells; a subset of human suppressor T-cells is also sensitive to ConA. ConA was the first lectin to be available on a commercial basis, and is widely used in biology and biochemistry to characterize glycoproteins and other sugar-containing entities on the surface of various cells. It is also used to purify glycosylated macromolecules in lectin affinity chromatography, as well as to study immune regulation by various immune cells.
Abrin is an extremely toxic toxalbumin found in the seeds of the rosary pea, Abrus precatorius. It has a median lethal dose of 0.7 micrograms per kilogram of body mass when given to mice intravenously. 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.
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Cetrimonium bromide ([(C16H33)N(CH3)3]Br; cetyltrimethylammonium bromide; hexadecyltrimethylammonium bromide; CTAB) is a quaternary ammonium surfactant.
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Rubroboletus satanas, commonly known as Satan's bolete or the Devil's bolete, is a basidiomycete fungus of the bolete family (Boletaceae) and one of its most infamous members. It was known as Boletus satanas before its transfer to the new genus Rubroboletus in 2014, based on molecular phylogenetic data. Found in broad-leaved and mixed woodland in the warmer regions of Europe, it is classified as a poisonous mushroom, known to cause gastrointestinal symptoms of diarrhea and violent vomiting. However, reports of poisoning are rare, due to its striking appearance and at times putrid smell, which discourage casual experimentation.
β2-glycoprotein 1, also known as beta-2 glycoprotein 1 and Apolipoprotein H (Apo-H), is a 38 kDa multifunctional plasma protein that in humans is encoded by the APOH gene. One of its functions is to bind cardiolipin. When bound, the structure of cardiolipin and β2-GP1 both undergo large changes in structure. Within the structure of Apo-H is a stretch of positively charged amino acids, Lys-Asn-Lys-Glu-Lys-Lys, are involved in phospholipid binding.
Basigin (BSG) also known as extracellular matrix metalloproteinase inducer (EMMPRIN) or cluster of differentiation 147 (CD147) is a protein that in humans is encoded by the BSG gene. This protein is a determinant for the Ok blood group system. There are three known antigens in the Ok system; the most common being Oka, OK2 and OK3. Basigin has been shown to be an essential receptor on red blood cells for the human malaria parasite, Plasmodium falciparum. The common isoform of basigin (basigin-2) has two immunoglobulin domains, and the extended form basigin-1 has three.
In molecular biology, hemagglutinins are receptor-binding membrane fusion glycoproteins produced by viruses in the Paramyxoviridae family. Hemagglutinins are responsible for binding to receptors on red blood cells to initiate viral attachment and infection. The agglutination of red cells occurs when antibodies on one cell bind to those on others, causing amorphous aggregates of clumped cells.
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 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.
Cnestis polyphylla, or itch pod, is a liane or scrambling shrub belonging to the family Connaraceae and occurring south from Kenya in East Tropical Africa through Mozambique and Zimbabwe to Southern Africa where it is found in coastal and escarpment forest in Limpopo, Mpumalanga, Eswatini and KwaZulu-Natal, and further south to the Eastern Cape. It also grows on the Indian Ocean islands of Madagascar, Mauritius and Réunion. The genus has at least 13 species with many still unresolved. They are distributed mainly in tropical Africa and nearby islands, but extend to SE Asia and China.
Volkensin is a eukaryotic ribosome-inactivating protein found in the Adenia volkensii plant. It is a glycoprotein with two subunits A and B. A subunit is linked to B subunit with disulfide bridges and non-covalent bonds. B subunit is responsible for binding to the galactosyl-terminated receptors on the cell membrane that allows the entry the A subunit of the toxin into the cell, which performs the inhibitory function. Volkensin is a galactose specific lectin that can inhibit protein synthesis in whole cells and in cell-free lysates. This protein can be included into the category of risin like toxins and it resembles modeccin, the toxin of Adenia digitata. Although very similar in composition, volkensin contains more cysteine residues and more than twice as much sugar than modeccin, due to high content of galactose and mannose. In addition, volkensin is able to inhibit protein synthesis at concentrations 10 times lower than required for modeccin. From gene sequencing analysis, volkensin was found to be coded by 1569-bp ORF, that is 523 amino acid residues without introns. The internal linker sequence is 45 bp. The active site of the A subunit contains Ser203, a novel residue that is conserved in all ribosome inactivating proteins.
Modeccin is a toxic lectin, a group of glycoproteins capable of binding specifically to sugar moieties. Different toxic lectins are present in seeds of different origin. Modeccin is found in the roots of the African plant Adenia digitata. These roots are often mistaken for edible roots, which has led to some cases of intoxication. Sometimes the fruit is eaten, or a root extract is drunk as a manner of suicide.
References
- ↑ Gachet, C.; Ennamany, R.; Kretz, O.; Ohlmann, P.; Krause, C.; Creppy, E. E.; Dirheimer, G.; Cazenave, J. P. (January 1996). "Bolesatine induces agglutination of rat platelets and human erythrocytes and platelets in vitro". Human & Experimental Toxicology. 15 (1): 26–29. doi:10.1177/096032719601500105. ISSN 0960-3271. PMID 8845205. S2CID 23915071.
- ↑ Kretz, Olivier; Creppy, Edmond Ekue; Dirheimer, Guy (January 1991). "Disposition of the toxic protein, bolesatine, in rats: its resistance to proteolytic enzymes". Xenobiotica. 21 (1): 65–73. doi:10.3109/00498259109039451. PMID 2003368.
- ↑ Kretz, Olivier; Creppy, Edmond Ekue; Dirheimer, Guy (February 1991). "Characterization of bolesatine, a toxic protein from the mushroom Boletus satanas Lenz and it's[sic] effects on kidney cells". Toxicology. 66 (2): 213–24. doi:10.1016/0300-483x(91)90220-u. PMID 1707561.
- ↑ Ennamany, R.; Lavergne, J.P.; Reboud, J.P.; Dirheimer, G.; Creppy, E.E. (June 1995). "Mode of action of bolesatine, a cytotoxic glycoprotein from Boletus satanas Lenz. Mechanistic approaches". Toxicology. 100 (1–3): 51–55. doi:10.1016/0300-483x(95)03058-n. ISSN 0300-483X. PMID 7624882.
- ↑ Licastro, Frederico; Morini, Maria Cristina; Kretz, Olivier; Dirheimer, Guy; Creppy, Edmond Ekue; Stirpe, Fiorenzo (May 1993). "Mitogenic activity and immunological properties of bolesatine, a lectin isolated from the mushroom Boletus satanas Lenz". International Journal of Biochemistry. 25 (5): 789–792. doi:10.1016/0020-711x(93)90366-m. PMID 8349019.
- ↑ Ennamany, R.; Marzetto, S.; Saboureau, D.; Creppy, E. E. (1995-12-01). "Lipid peroxidation induced by bolesatine, a toxin ofBoletus satanas: Implication in m5dC variation in Vero cells related to inhibition of cell growth". Cell Biology and Toxicology. 11 (6): 347–354. doi:10.1007/BF01305906. ISSN 1573-6822. PMID 8788210. S2CID 20541517.
- ↑ Ennamany, R.; Bingen, A.; Creppy, E. E.; Kretz, O.; Gut, J. P.; Dubuisson, L.; Balabaud, C.; Bioulac Sage, P.; Kirn, A. (November 1998). "Aspirin and heparin prevent hepatic blood stasis and thrombosis induced by the toxic glycoprotein Bolesatine in mice". Human & Experimental Toxicology. 17 (11): 620–624. doi:10.1177/096032719801701106. ISSN 0960-3271. PMID 9865419. S2CID 43529948.
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