Department of Biochemistry, Center for Biomedical Mass Spectrometry and ‡Bioinformatics Program, Boston University , Boston, Massachusetts 02215, United States.
Anal Chem. 2017 Jun 20;89(12):6645-6655. doi: 10.1021/acs.analchem.7b00875. Epub 2017 Jun 6.
Glycomics and glycoproteomics analyses by mass spectrometry require efficient front-end separation methods to enable deep characterization of heterogeneous glycoform populations. Chromatography methods are generally limited in their ability to resolve glycoforms using mobile phases that are compatible with online liquid chromatography-mass spectrometry (LC-MS). The adoption of capillary electrophoresis-mass spectrometry methods (CE-MS) for glycomics and glycoproteomics is limited by the lack of convenient interfaces for coupling the CE devices to mass spectrometers. Here, we describe the application of a microfluidics-based CE-MS system for analysis of released glycans, glycopeptides and monosaccharides. We demonstrate a single CE method for three different modalities, thus contributing to comprehensive glycoproteomics analyses. In addition, we explored compatible sample derivatization methods. We used glycan TMT-labeling to improve electrophoretic migration and enable multiplexed quantitation by tandem MS. We used sialic acid linkage-specific derivatization methods to improve separation and the level of information obtained from a single analytical step. Capillary electrophoresis greatly improved glycoform separation for both released glycans and glycopeptides over that reported for chromatography modes more frequently employed for such analyses. Overall, the CE-MS method described here enables rapid setup and analysis of glycans and glycopeptides using mass spectrometry.
糖组学和糖蛋白质组学的质谱分析需要高效的前端分离方法，以实现对异质糖型群体的深入表征。色谱法通常受到限制，因为它们无法使用与在线液相色谱-质谱联用（LC-MS）兼容的流动相来解析糖型。毛细管电泳-质谱法（CE-MS）在糖组学和糖蛋白质组学中的应用受到缺乏方便的接口将 CE 设备与质谱仪连接的限制。在这里，我们描述了一种基于微流控的 CE-MS 系统在释放糖、糖肽和单糖分析中的应用。我们展示了一种用于三种不同模式的单一 CE 方法，从而有助于全面的糖蛋白质组学分析。此外，我们还探索了兼容的样品衍生化方法。我们使用聚糖 TMT 标记来改善电泳迁移并通过串联 MS 实现多重定量。我们使用唾液酸键特异性衍生化方法来改善分离效果，并从单个分析步骤中获得更多信息。与更频繁用于此类分析的色谱模式相比，毛细管电泳大大改善了释放糖和糖肽的糖型分离。总体而言，这里描述的 CE-MS 方法可使用质谱法快速设置和分析聚糖和糖肽。
