Decoding Protein Gas-Phase Stability with Alanine Scanning and Collision-Induced Unfolding Ion Mobility Mass Spectrometry
Decoding Protein Gas-Phase Stability with Alanine Scanning and Collision-Induced Unfolding Ion Mobility Mass Spectrometry
复制标题
利用丙氨酸扫描和碰撞诱导展开离子淌度质谱解码蛋白质气相稳定性
DOI：
10.1002/anse.202000019
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发表时间：
2020
期刊：
影响因子：
--
通讯作者：
Bellamy-Carter J
中科院分区：
文献类型：
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作者：
Bellamy-Carter J
天然质谱是结构生物学中广泛使用的工具，通过在气相中保存复合物来提供有关蛋白质结构和相互作用的信息。在此，通过丙氨酸扫描和碰撞诱导解折叠（CIU）离子淌度质谱研究了气相中分子内非共价相互作用的重要性。发现酰基载体蛋白（ACP）表面上特定极性和离子残基的突变会破坏致密气相结构的稳定性，其中突变体 E31A、D32A、D41A 和 D65A 尤其不稳定。 ACP 7+ 和 8+ 离子的分子动力学模拟显示，由于极性表面残基的侧链塌陷而导致分子内相互作用延长，这种相互作用仅限于气相，与 CIU 数据一致。这些发现为特定离子残基及其相互作用在维持紧凑的蛋白质气相结构中的重要性提供了证据。
Native mass spectrometry is a widely used tool in structural biology, providing information on protein structure and interactions through preservation of complexes in the gas phase. Herein, the importance of intramolecular non‐covalent interactions in the gas phase has been studied by alanine scanning and collision‐induced unfolding (CIU) ion mobility‐mass spectrometry. Mutation of specific polar and ionic residues on the surface of an acyl carrier protein (ACP) were found to destabilise the compact gas‐phase structure with mutants E31A, D32A, D41A and D65A being particularly destabilised. Molecular dynamics simulations of the ACP 7+ and 8+ ions showed extended intramolecular interactions, resulting from sidechain collapse of polar surface residues, which were confined to the gas phase and consistent with the CIU data. These findings provide evidence for the importance of specific ionic residues, and their interactions, in the maintenance of compact protein gas‐phase structure.