REFINED STRUCTURE OF CHARYBDOTOXIN - COMMON MOTIFS IN SCORPION TOXINS AND INSECT DEFENSINS
REFINED STRUCTURE OF CHARYBDOTOXIN - COMMON MOTIFS IN SCORPION TOXINS AND INSECT DEFENSINS
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DOI：
10.1126/science.1720574
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发表时间：
1991-12-06
期刊：
影响因子：
56.9
通讯作者：
TOMA, F
中科院分区：
文献类型：
--
作者：
BONTEMS, F;ROUMESTAND, C;TOMA, F
K+通道阻断剂-用DIANA和X-PLOR方法计算了新的质子核磁共振（NMR）数据，得到了描述Chtx三级结构的高分辨率模型。该蛋白具有一个小的三链反平行β-折叠，分别通过两个二硫键连接到短螺旋和一个二硫键连接到延伸片段。这个基序也存在于所有已知的蝎毒素结构中，无论它们的大小，序列和功能如何。引人注目的是，抗菌昆虫防御素也采用这种折叠模式。
Conflicting three-dimensional structures of charybdotoxin (Chtx), a blocker of K+ channels, have been previously reported. A high-resolution model depicting the tertiary structure of Chtx has been obtained by DIANA and X-PLOR calculations from new proton nuclear magnetic resonance (NMR) data. The protein possesses a small triple-stranded antiparallel beta-sheet linked to a short helix by two disulfides and to an extended fragment by one disulfide, respectively. This motif also exists in all known structures of scorpion toxins, irrespective of their size, sequence, and function. Strikingly, antibacterial insect defensins also adopt this folding pattern.