Native mass spectrometry (nMS) is increasingly used for studies of large biomolecules (>100 kDa), especially proteins and protein complexes. The growth in this area can be attributed to advances in native electrospray ionization as well as instrumentation that is capable of accessing high mass-to-charge (m/z) regimes without significant losses in sensitivity and resolution. Here, we describe modifications to the ESI source of an Agilent 6545XT Q-TOF MS that is tailored for analysis of large biomolecules. The modified ESI source was evaluated using both soluble and membrane protein complexes ranging from ~127 to ~232 kDa and the ~801 kDa protein chaperone GroEL. The increased mass resolution of the instrument affords the ability to resolve small molecule adducts and analyze collision-induced dissociation products of the native complexes.

中文翻译：

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在扩展质量范围 Q-TOF MS 上开发原生 MS 功能

天然质谱 (nMS) 越来越多地用于研究大生物分子 (>100 kDa)，尤其是蛋白质和蛋白质复合物。该领域的增长可归因于本机电喷雾电离以及能够获得高质荷比 (m/z) 机制而不会显着降低灵敏度和分辨率的仪器的进步。在这里，我们介绍了对 Agilent 6545XT Q-TOF MS 的 ESI 源的修改，该质谱是专为分析大生物分子而设计的。使用范围从 ~127 到 ~232 kDa 的可溶性和膜蛋白复合物和 ~801 kDa 蛋白伴侣 GroEL 对改良的 ESI 源进行了评估。仪器提高的质量分辨率提供了解析小分子加合物和分析天然复合物的碰撞诱导解离产物的能力。