Proteoforms contribute functional diversity to the proteome and aberrant proteoforms levels have been implicated in biological dysfunction and disease. Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR MS), with its ultrahigh mass-resolving power, mass accuracy, and versatile tandem MS capabilities, has empowered top-down, middle-down, and native MS-based approaches for characterizing proteoforms and their complexes in biological systems. Herein, we review the features which make FT-ICR MS uniquely suited for measuring proteoform mass with ultrahigh resolution and mass accuracy; obtaining in-depth proteoform sequence coverage with expansive tandem MS capabilities; and unambiguously identifying and localizing post-translational and noncovalent modifications. We highlight examples from our body of work in which we have quantified and comprehensively characterized proteoforms from cardiac and skeletal muscle to better understand conditions such as chronic heart failure, acute myocardial infarction, and sarcopenia. Structural characterization of monoclonal antibodies and their proteoforms by FT-ICR MS and emerging applications, such as native top-down FT-ICR MS and high-throughput top-down FT-ICR MS-based proteomics at 21 T, are also covered. Historically, the information gleaned from FT-ICR MS analyses have helped provide biological insights. We predict FT-ICR MS will continue to enable the study of proteoforms of increasing size from increasingly complex endogenous mixtures and facilitate the benchmarking of sensitive and specific assays for clinical diagnostics. © 2020 John Wiley & Sons Ltd. Mass Spec Rev

中文翻译：

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傅立叶变换离子回旋共振质谱法表征蛋白质

蛋白质组为蛋白质组贡献了功能多样性，异常的蛋白质组水平与生物功能障碍和疾病有关。傅里叶变换离子回旋共振质谱 (FT-ICR MS) 具有超高的质量分辨能力、质量精度和多功能的串联 MS 功能，使自上而下、中下和基于 MS 的方法能够用于表征生物系统中的蛋白质及其复合物。在此，我们回顾了使 FT-ICR MS 独特地适用于以超高分辨率和质量精度测量蛋白质质量的特征；通过广泛的串联 MS 功能获得深入的蛋白质序列覆盖；并明确识别和定位翻译后和非共价修饰。我们重点介绍了我们工作中的例子，在这些例子中，我们量化并全面表征了心肌和骨骼肌的蛋白质形式，以更好地了解慢性心力衰竭、急性心肌梗塞和肌肉减少症等疾病。还涵盖了通过 FT-ICR MS 和新兴应用（例如原生自上而下 FT-ICR MS 和高通量自上而下基于 FT-ICR MS 的 21 T 蛋白质组学）对单克隆抗体及其蛋白质形式的结构表征。从历史上看，从 FT-ICR MS 分析中收集的信息有助于提供生物学见解。我们预测 FT-ICR MS 将继续支持从越来越复杂的内源性混合物中研究越来越大的蛋白质组，并促进临床诊断的敏感和特异性检测的基准测试。© 2020 John Wiley & Sons Ltd.