Structural basis of ligand binding and release in insect pheromone-binding proteins:: NMR structure of Antheraea polyphemus PBP1 at pH 4.5
Structural basis of ligand binding and release in insect pheromone-binding proteins:: NMR structure of Antheraea polyphemus PBP1 at pH 4.5
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DOI：
10.1016/j.jmb.2007.07.078
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发表时间：
2007-11-02
影响因子：
5.6
通讯作者：
Wuethrich, Kurt
中科院分区：
文献类型：
--
作者：
Damberger, Fred F.;Ishida, Yuko;Wuethrich, Kurt
在20 ℃下测定了pH 4.5的天蚕信息素结合蛋白1 ApolPBP 1（A）的NMR结构。该结构由六个α-螺旋组成，其排列成球状折叠，该球状折叠包封由C-末端多肽区段131-142形成的中心螺旋α 7。这些螺旋的3D排列通过三个二硫键19-54、50-108和97-117锚定，这三个二硫键通过NMR鉴定。ApolPBP 1（A）结构与pH4.5的家蚕同源信息素结合蛋白BmorPBP（A）的结构的叠加产生了1.7埃的rmsd，计算的骨架重原子N、C-α和残基10-142的C'。相比之下，目前的ApolPBP 1（A）结构与最近提出的不含中心螺旋α 7的低pH形式的ApolPBP 1分子模型不同。ApolPBP 1在NMR化学位移时间尺度上类似于BmorPBP的缓慢交换中表现出两种不同球状构象之间的pH依赖性转变，这表明这两种蛋白质使用相同的配体结合和排出机制。广泛的序列同源性观察信息素结合蛋白从蛾物种进一步意味着，先前提出的配体弹射机制，涉及插入的C-末端螺旋到信息素结合位点是一个一般的功能信息素信号在蛾。(C)2007爱思唯尔有限公司保留所有权利。
The NMR structure of the Antheraea polyphemus pheromone-binding protein 1 at pH 4.5, ApolPBP1(A), was determined at 20 degrees C. The structure consists of six alpha-helices, which are arranged in a globular fold that encapsulates a central helix alpha 7 formed by the C-terminal polypeptide segment 131-142. The 3D arrangement of these helices is anchored by the three disulfide bonds 19-54, 50-108 and 97-117, which were identified by NMR. Super-position of the ApolPBP1(A) structure with the structure of the homologous pheromone-binding protein of Bombyx mori at pH 4.5, BmorPBP(A), yielded an rmsd of 1.7 angstrom calculated for the backbone heavy-atoms N, C-alpha and C' of residues 10-142. In contrast, the present ApolPBP1(A) structure is different from a recently proposed molecular model for a low-pH form of ApolPBP1 that does not contain the central helix alpha 7. ApolPBP1 exhibits a pH-dependent transition between two different globular conformations in slow exchange on the NMR chemical shift timescale similar to BmorPBP, suggesting that the two proteins use the same mechanism of ligand binding and ejection. The extensive sequence homology observed for pheromone-binding proteins from moth species further implies that the previously proposed mechanism of ligand ejection involving the insertion of a C-terminal helix into the pheromone-binding site is a general feature of pheromone signaling in moths. (C) 2007 Elsevier Ltd. All rights reserved.