黑腹胡蜂乃是國內最危險、最具攻擊性的蜂種之一，其蜂毒經廣泛的研究之後，發現極具醫藥價值。黑腹胡蜂的蜂毒中，最主要的一種成分就是Mastoparan B(簡稱MP-B)。MP-B的功能非常多樣，像是與A2、C磷脂酶的活化、溶血作用、組織胺的釋放及活化G蛋白等。MP-B是一種由14個胺基酸(LKLKSIVSWAKKVL-CONH2)所組成且帶正電的多肽類分子，可形成具二向性(amphiphilic)的α-螺旋構形，一面呈疏水性，另一面呈親水性。根據前人的研究指出，MP-B在水中其結構會呈現相當的不穩定性，在三氟乙醇(TFE)與水的混合溶液中則會相當穩定呈現α-螺旋的構形。由於大多數關於結構上的實驗，僅限於對於MP-B接在細胞膜上時所呈現之構形的探討，對於MP-B與細胞膜之間相互作用的描述相當缺乏，因此吾人希望透過分子動力學模擬的研究方法，嘗試著先模擬MP-B在類細胞膜環境-TFE溶液中的行為，以探究這當中的機制。根據30奈秒的模擬過程顯示，單一MP-B分子在純TFE溶液環境的不穩定性，很有可能是提供MP-B分子得以溶解細胞膜的重要因素。

In Taiwan, the black-bellied hornet (Vespa basalis) is certainly the most dangerous and aggressive one in all species of vespine wasp. It has been found that its venom possesses important medicinal values by diversely researches. Mastoparan B (MP-B) is the major component of venom of Vespa basalis, which has shown various functions, such as activation of phospholipase A2 and C, erythrocyte lysis, histamine release, and activation of G-proteins. MP-B is a kind of cationic tetradecapeptide, which can form amphiphilic α-helix with hydrophilic residues on one side and hydrophobic ones on the other side. According to former researches, MP-Bs are random coil in aqueous solution and adopt α-helix conformation in the presence of trifluoroethanol (TFE). Notwithstanding so many research works about the relationship of structure-function of MP-B, mainly about the conformation of MP-B's binding to membrane, the detailed dynamical informations of MP-B in membrane-like environment and interactions of MP-B with membrane are still poor. Therefore, I tried to simulate MP-B in TFE/water mixtures by molecular dynamics to insight into the mechanism of membrane-perturbation of MP-B. My 30ns simulation have shown that the unstability of MP-B in high concentration of TFE/water mixtures may be a critical factor in the interaction of MP-B with membrane.

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