Resolving Isomeric Posttranslational Modifications Using a Biological Nanopore as a Sensor of Molecular Shape
Resolving Isomeric Posttranslational Modifications Using a Biological Nanopore as a Sensor of Molecular Shape
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DOI：
10.1021/jacs.2c06211
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发表时间：
2022-08-25
影响因子：
15
通讯作者：
Behrends, Jan C.
中科院分区：
文献类型：
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作者：
Ensslen, Tobias;Sarthak, Kumar;Behrends, Jan C.
蛋白质或肽中翻译后修饰 (PTM) 的化学性质和精确位置对于癌症等各种严重疾病至关重要。最先进的 PTM 诊断基于复杂且昂贵的质谱或基于免疫分析的方法，这些方法的选择性和特异性有限。在这里，我们展示了使用蛋白质纳米孔根据乙酰化和甲基化赖氨酸残基的位置来区分相同质量的源自人组蛋白 H4 蛋白的肽。与逐步线程测序不同，我们的方法通过感测完全捕获的肽的形状来检测 PTM 及其位置，从而消除了受控易位的需要。分子动力学模拟表明，对分子形状的敏感性源自沿孔的高度不均匀的电场。这种分子形状传感原理为蛋白质亚型的多功能、无标记和高通量表征提供了途径。
The chemical nature and precise position of posttranslational modifications (PTMs) in proteins or peptides are crucial for various severe diseases, such as cancer. State-of-the -art PTM diagnosis is based on elaborate and costly mass-spectrometry or immunoassay-based approaches, which are limited in selectivity and specificity. Here, we demonstrate the use of a protein nanopore to differentiate peptides-derived from human histone H4 protein -of identical mass according to the positions of acetylated and methylated lysine residues. Unlike sequencing by stepwise threading, our method detects PTMs and their positions by sensing the shape of a fully entrapped peptide, thus eliminating the need for controlled translocation. Molecular dynamics simulations show that the sensitivity to molecular shape derives from a highly nonuniform electric field along the pore. This molecular shape-sensing principle offers a path to versatile, label-free, and high-throughput characterizations of protein isoforms.