Coil-to-helix transition and ligand release of Bombyx mori pheromone-binding protein
Coil-to-helix transition and ligand release of Bombyx mori pheromone-binding protein
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DOI：
10.1016/j.bbrc.2005.07.176
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发表时间：
2005-10-07
影响因子：
3.1
通讯作者：
Clardy, J
中科院分区：
文献类型：
--
作者：
Lautenschlager, C;Leal, WS;Clardy, J
疏水性昆虫信息素通过其受体周围的水介质运输是由信息素结合蛋白(PBPs)辅助的。家蚕蛾BmorPBP蛋白具有依赖于pH的构象变化，可以触发信息素Bombykol向其受体的释放。在低pH时，α-螺旋占据着与高pH时BmorPBP-ombykol复合体中信息素相同的结合口袋。我们测定了apo BmorPBP的晶体结构，其分辨率为2.3埃，pH为7.5，其结构与A-型惊人地相似。这些数据表明，除了先前描述的pH依赖的构象变化外，BmorPBP还经历了配体依赖的构象变化。对占据结合口袋的α-螺旋的分析表明，一个两亲性螺旋在一个面上有三个酸性残基，这些残基在鳞翅目多酚中保守，可能参与了BmorPBP在受体膜上的构象转变。(C)2005 Elsevier Inc.保留所有权利。
The transport of hydrophobic insect pheromones through the aqueous medium surrounding their receptors is assisted by pheromone-binding proteins (PBPs). The protein from the silkworm moth Bombyx mori, BmorPBP, exhibits a pH-dependent conformational change postulated to trigger the release of the pheromone bombykol to its receptor. At low pH, an alpha-helix occupies the same binding pocket that houses the pheromone in the BmorPBP-bombykol complex at high pH. We have determined the crystal structure of apo BmorPBP at a resolution of 2.3 angstrom and pH 7.5, which has surprisingly a structure similar to the A-form. These data suggest that BmorPBP undergoes a ligand-dependent conformational change in addition to the previously described pH-dependent conformational change. Analysis of the alpha-helix occupying the binding pocket reveals an amphipathic helix with three acidic residues along one face that are conserved among lepidopteran PBPs and may be involved in a conformational transition of BmorPBP at the receptor membrane. (c) 2005 Elsevier Inc. All rights reserved.