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Taicatoxin (TCX) is a snake toxin that blocks voltage-dependent L-type calcium channels and small conductance Ca2+-activated K+ channels. The name taicatoxin (TAIpan + CAlcium + TOXIN) is derived from its natural source, the taipan snake, the site of its action, calcium channels, and from its function as a toxin. Taicatoxin was isolated from the venom of Australian taipan snake, ''Oxyuranus scutellatus scutellatus''. TCX is a secreted protein, produced in the venom gland of the snake. == Chemistry == Through SDS-PAGE analysis, TCX () was determined to be a complex held together by non-covalent forces of the following three polypeptides in a stoichiometry of 1:1:4 respectively: * a α-neurotoxin-like peptide (8 kDa), * a neurotoxic phospholipase (16 kDa; UniProt ), and * a serine protease inhibitor (7 kDa; UniProt ). The active complex was isolated by ion exchange chromatography through DE-Cellulose and two steps of Cm-Cellulose chromatography at pH = 4.7 and pH = 6.0, respectively. It migrates in beta-alanine-acetate-urea gel electrophoresis as a single compound. The phospholipase activity can be separated by affinity chromatography, using a phospholipid analog (PC-Sepharose). The alpha-neurotoxin-like peptide can be separated from the protease inhibitor, Sephadex G-50 gel filtration chromatography can be used, in the presence of high salt (1M NaCl) and alkaline conditions (pH = 8.2). The amino sequence of the protease inhibitor was determined by using the automatic Edman degradation method. 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「Taicatoxin」の詳細全文を読む スポンサード リンク
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