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Mambalgins are peptides in the venom of the deadly African snake known as Black Mamba (Dendroaspis polylepsis), from the Elapidae family. This peptide toxin was discovered, after a number of experiments carried out with venoms of a wide range of snakes, by Dr. Sylvie Diochot in a group of researchers of Niza (France), directed by Dr. Eric Lingueglia.〔Nature. "Black mamba venom peptides target acid-sensing ion channels to abolish pain".()〕 This discovery surprised the researchers because mambalgins have a potent analgesic effect,〔(Nature. "Black mamba takes away pain" )〕 which is not typical of such a deadly and dangerous reptile, given that many other snakes instead of omitting pain, produce it in great measure.〔Nature. "A heteromeric Texas coral snake toxin targets acid-sensing ion channels to produce pain." ()〕 The researchers named the peptide by combining ''mamba'' (the name of the snake), and ''algin'' (analgesic power). ==Structure== Mambalgins are classified as being part of the family of three-finger toxins.〔 This type of peptide toxin is found in snake venoms (specifically in black mambas) and is characterised by its distinctive structure. As far as we know, there are two isoforms of mambalgin which have been given the names of mambalgin-1 and mambalgin-2. Both of these isopeptides are made of a 57 aminoacidic chain with 8 residues of cysteine. These two isoforms differ only in the residue located in the fourth position of the chain.〔 Mambalgin-1 presents a three-dimensional structure of three loops that emerge from the nucleus of this protein. A triple chain with antiparallel β-sheets connects loops II and III, and a double chain, also formed by antiparallel β-sheets, allows the formation and bonding of loop I. Moreover, the protein presents a concave area, which is typical of neurotoxins, stabilized by four disulphide bonds.〔 Mambalgins also show a high electrostatic potential, which is necessary for bonding with the ASIC ionic channels, which are negatively charged. Before mambalgins were discovered, other toxins also related to the interaction with ASIC channels had already been known (PcTx1 and APETx2). Nevertheless, scientists have proved that mambalgins do not share the same amino acid sequences as these other ASIC related toxins, but are rather more similar in structure to proteins found in the venom of cobras. Specifically, the DNA sequence of mambalgins has a 55% coincidence with the sequence in proteins CM-3 and CM-2a of Naja Haje annulifera and a 47% coincidence with the CM-1b protein and the alpha-neurotoxin OH-26 of Hemachatus Haemachatus and Ophiophagus Hannah, respectively. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Mambalgins」の詳細全文を読む スポンサード リンク
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