Development of antibacterial drugs based on insect antibacteria proteins

肉毒素I是一种强有力的抗菌蛋白质，它是在用皮下针刺异色麻蝇幼虫体壁时在血淋巴中诱导产生的。我们将该蛋白纯化至均一，发现它由三种蛋白质组成，称为肌毒素IA，IB和IC，具有几乎相同的一级结构。将每个组分纯化至均一，并测定其氨基酸序列。结果表明，每个蛋白质由39个氨基酸残基组成，3个蛋白质之间的差异仅在2 - 3个氨基酸残基之间。在E. coli，E.大肠杆菌几乎瞬间消失，导致主动运输和ATP产生的损失。因此，我们认为，肌毒素I是一种非常有用的物质，它有许多用途，包括抗菌药物。

Sarcotoxin I is a potent antibacterial protein induced in the hemolymph of Sarcophaga peregrina larvae when their body wall was pricked with a hypodermic needle. We purified this protein to homogeneity and found that it consists of three proteins termed sarcotoxin IA, IB and IC having almost identical primary structure. Each component was purified to homogeneity and its amino acid sequence was determined. It was found that each protein consists of 39 amino acid residues and difference among three proteins is in only 2 - 3 amino acid residues.Primary site of sarcotoxin I was shown to be bacterial membrane. On addition of sarcotoxin I to E. coli, mimbrane potential of E. coli disappeared almost instantaneously, resulting in the loss of active transport and ATP generation. A cDNA clone for sarcotoxin IA has been isolated.In summary, we concluded that sarcotoxin I is a very useful substance and there are many applications of this substance including antibacterial drugs.