Hydrogen bond-based smart polymer for highly selective and tunable capture of multiply phosphorylated peptides

Guangyan Qing, Qi Lu, Xiuling Li*, Jing Liu, Mingliang Ye, Xinmiao Liang* and Taolei Sun*

Nat. Commun., 2017, 8, 461

DOI: 10.1038/s41467-017-00464-0

Multisite phosphorylation is an important and common mechanism for finely regulating protein functions and subsequent cellular responses. However, this study is largely restricted by the difficulty to capture low-abundance multiply phosphorylated peptides (MPPs) from complex biosamples owing to the limitation of enrichment materials and their interactions with phosphates. Here we show that smart polymer can serve as an ideal platform to resolve this challenge. Driven by specific but tunable hydrogen bonding interactions, the smart polymer displays differential complexation with MPPs, singly phosphorylated and non-modified peptides. Importantly, MPP binding can be modulated conveniently and precisely by solution conditions, resulting in highly controllable MPP adsorption on material surface. This facilitates excellent performance in MPP enrichment and separation from model proteins and real biosamples. High enrichment selectivity and coverage, extraordinary adsorption capacities and recovery towards MPPs, as well as high discovery rates of unique phosphorylation sites, suggest its great potential in phosphoproteomics studies.

基于氢键的智能聚合物用于高度选择性和可调节地捕获多磷酸化肽

多位点磷酸化是精细调节蛋白质功能和随后的细胞反应的重要且常见的机制。然而，由于富集材料的限制及其与磷酸盐的相互作用，该研究在很大程度上受到从复杂生物样品中捕获低丰度多磷酸化肽（MPP）的困难的限制。在这里，我们展示智能聚合物可以作为解决这一挑战的理想平台。由特定但可调节的氢键相互作用驱动，智能聚合物显示与MPP，单磷酸化和未修饰肽的差异络合。重要的是，MPP结合可以通过溶液条件方便且精确地调节，从而在材料表面上产生高度可控的MPP吸附。这有助于MPP富集和从模型蛋白质和真实生物样品中分离的优异性能。高浓缩选择性和覆盖率，非凡的吸附能力和向MPP的回收，以及独特的磷酸化位点的高发现率，表明其在磷酸蛋白质组学研究中的巨大潜力。