Native ESI-MS and Collision Induced Unfolding (CIU) of the Complex between Bacterial Elongation Factor-Tu and the Antibiotic Enacyloxin IIa

Raw native-MS and IM-MS data supporting publication in JASMS. Abstract: Collision induced unfolding (CIU) of protein ions, monitored by ion mobility-mass spectrometry (IM-MS), can be used to assess the stability of their compact gas-phase fold, and hence provide structural information. The bacterial elongation factor EF-Tu, a key protein for protein translation in prokaryotes, and hence a promising antibiotic target, has been studied by CIU. The major [M+12H]12+ ion of EF-Tu unfolded in collision with Ar atoms between 40 and 50 V, corresponding to an Elab energy of 480-500 eV. Binding of the cofactor analogue GDPNP and the antibiotic enacyloxin IIa stabilized the compact fold of EF-Tu, although dissociation of the latter from the complex diminished its stabilizing effect at higher collision energies

支持发表于《美国质谱学会志》（JASMS）的原始天然质谱（native-MS）与离子淌度质谱（ion mobility-mass spectrometry, IM-MS）数据。摘要：通过离子淌度质谱（IM-MS）监测的蛋白质离子碰撞诱导解折叠（collision induced unfolding, CIU）技术，可用于评估其紧凑气相折叠构象的稳定性，进而提供结构相关信息。本研究针对原核生物蛋白质翻译过程中的关键蛋白、同时亦是极具潜力的抗生素靶点的细菌延伸因子EF-Tu开展了CIU研究。EF-Tu的主要[M+12H]12+离子在与氩原子发生碰撞、碰撞电压介于40 V至50 V时发生解折叠，对应的实验室系碰撞能量（Elab energy）为480 eV至500 eV。辅因子类似物GDPNP与抗生素恩阿洛辛IIa（enacyloxin IIa）的结合能够稳定EF-Tu的紧凑折叠构象，尽管后者从复合物上解离后，其在较高碰撞能量下的稳定作用会有所削弱。