Highly Selective Capture of Monophosphopeptides by Two-Dimensional Metal-Organic Framework Nanosheets
Highly Selective Capture of Monophosphopeptides by Two-Dimensional Metal-Organic Framework Nanosheets
复制标题
DOI：
10.1021/acs.analchem.9b01581
复制
发表时间：
2019-07-16
影响因子：
7.4
通讯作者：
Gu, Zhi-Yuan
中科院分区：
文献类型：
--
作者：
Xiao, Jing;Yang, Shi-Shu;Gu, Zhi-Yuan
复杂生物样品中单磷酸肽与多磷酸肽的分离对于蛋白激酶信号转导途径的研究具有重要意义。据我们所知，很少有材料能够选择性地富集单磷酸肽，因为在酸性条件下保留中间单磷酸肽并排除非磷酸肽和多磷酸肽存在化学困难，这需要独特的相互作用来平衡金属亲和力和疏水性。合理选择二维（2-D）金属有机骨架（MOF）Hf-1,3,S-三（4-羧基苯基）苯（BTB）纳米片具有大表面积、丰富的活性位点和超薄结构。由于有机配体的伸长以及簇的金属亲和力与配体的疏水性之间的平衡，2-D Hf-BTB 纳米片对单磷酸肽表现出独特的富集选择性。 2-D MOF 纳米片在磷酸肽富集模型中表现出出色的灵敏度（检测限为 0.4 fmol mu L-1）和选择性[β-酪蛋白/BSA（牛血清白蛋白）摩尔比为 1:1000]。这些纳米片用于分析脱脂牛奶和人唾液样本，并对肛管炎症患者血清中失调的磷酸肽进行原位同位素标记，与对照健康血清相比，血清磷酸肽 HS4 (ADpSGEGDFLAEGGGVR) 上调 6.6 倍。使用 2-D Hf-BTB 纳米片进一步对来自 Akt（蛋白激酶 B）条件敲除小鼠和同窝对照小鼠的与阿尔茨海默病相关的小鼠脑皮质样本进行蛋白质组学分析。该方法对单磷酸肽的捕获效率很高，能够区分 Akt 敲除样品和对照样品之间单磷酸肽和微管相关蛋白 tau (MAPT/tau) 的差异。
Separation of monophosphopeptides from multi-phosphopeptides in complex biological samples is significant in the study of protein kinase signal transduction pathways. To the best of our knowledge, very few materials have been reported that could selectively enrich monophosphopeptides because of the chemical difficulty in retaining the intermediate monophosphopeptides and excluding both non-phosphopeptides and multi-phosphopeptides in acidic conditions, which requires unique interactions to balance the metallic affinity and the hydrophobicity. With the large surface area, abundant accessible active sites, and ultrathin structures, two-dimensional (2-D) metal-organic framework (MOF) Hf-1,3,S-tris(4-carboxyphenyl)benzene (BTB) nanosheets were rationally selected. Due to the elongated organic ligands and the balance between metallic affinity of clusters and hydrophobicity from ligands, the 2-D Hf-BTB nanosheets exhibited unique enrichment selectivity toward monophosphopeptides. The 2-D MOF nanosheets demonstrated excellent sensitivity (detection limit of 0.4 fmol mu L-1) and selectivity [1:1000 molar ratios of beta-casein/BSA (bovine serum albumin)] in model phosphopeptides enrichment. The nanosheets were implemented for the analysis of nonfat milk and human saliva samples as well as in situ isotope labeling for dysregulated phosphopeptides from patients' serum with anal canal inflammation, exhibiting 6.6-fold upregulation of serum phosphopeptide HS4 (ADpSGEGDFLAEGGGVR) compared to the control healthy serum. The proteomics analysis of mouse brain cortical samples associated with Alzheimer's disease, which were from Akt (protein kinase B) conditional knockout mouse and littermate control mouse, was further established with 2-D Hf-BTB nanosheets. With high capture efficiency for monophosphopeptides, this method was capable of distinguishing the difference of monophosphopeptides from microtubule-associated protein tau (MAPT/tau) between the Akt knockout sample and control sample.