Robust, Reproducible, and Economical Phosphopeptide Enrichment Using Calcium Titanate

Mass-spectrometry-based
phosphoproteomics has revolutionized phosphoprotein
analysis and enhanced our understanding of diverse and fundamental
cellular processes important for human health and disease. Because
of their relative scarcity, phosphopeptides must be enriched before
analysis. Many different enrichment methods and materials have been
described, and many reports have made claims about the advantages
of particular materials and methodological variations. We demonstrate
an effective and highly reproducible single-step enrichment method
using an off-the-shelf preparation of calcium titanate. Using two
different cell lines and replicate analysis, we show that our method
achieves a purity and depth of analysis comparable or superior to
a widely used TiO2-based method at a reduced cost and effort.
This method provides a new and immediately available tool for expanding
the reach of phosphoproteomic inquiry.

基于质谱的磷酸化蛋白质组学（mass-spectrometry-based phosphoproteomics）极大地革新了磷酸化蛋白质分析研究，深化了我们对诸多与人类健康和疾病密切相关的核心细胞过程的认知。鉴于磷酸肽相对稀缺，分析前需对其进行富集。目前已报道了多种富集方法与富集材料，诸多研究均声称特定材料及方法变体具有独特优势。本研究展示了一种高效且重现性极佳的单步富集方法，该方法采用市售的钛酸钙制剂。通过使用两种不同细胞系开展重复分析实验，我们证实该方法的分析纯度与鉴定深度可与广泛使用的二氧化钛（TiO2）基方法媲美甚至更优，且成本更低、操作更简便。该方法为拓展磷酸化蛋白质组学研究的应用范围提供了一种全新且可即时获取的工具。