西湖大学吴明轩团队开发出一种实现深度覆盖甲基赖氨酸蛋白质组的化学选择性富集策略。相关研究成果发表在2024年7月16日出版的国际学术期刊《德国应用化学》。

蛋白质组学是一种全面了解细胞翻译后修饰（PTMs）的强大方法。由于丰度低，含有PTMs的胰蛋白酶肽通常会通过LC-MS/MS富集以提高覆盖率。通过金属氧化物对磷酸蛋白质组的亲和层析和赖氨酸乙酰基的泛特异性抗体可以鉴定数万个修饰位点。赖氨酸甲基化是一种重要的PTM，然而，从现有的方法中只鉴定出数百个甲基化位点。

该文中，研究人员报告了一种基于芳基重氮的化学选择性策略，该策略能够通过共价键以极高的灵敏度富集单甲基赖氨酸（Kme1）肽。研究人员从不同的细胞系和小鼠组织中鉴定出一万多种Kme1肽，表明赖氨酸甲基化对细胞过程有广泛的影响。此外，通过同位素标记实验，研究发现了大量不依赖S-腺苷甲硫氨酸（SAM）的甲基标记。因此，该方法为赖氨酸甲基化研究和新的生物学发现的广泛应用铺平了道路。

附：英文原文

Title: A chemo-selective enrichment strategy to achieve in-depth coverage of methyllysine proteome

Author: Lufeng Yan, Manqian Zheng, Mingzhu Fan, Rui Yao, Kun Zou, Shan Feng, Mingxuan Wu

Issue&Volume: 2024-07-16

Abstract: Proteomics is a powerful method to comprehensively understand cellular posttranslational modifications (PTMs). Due to low abundance, tryptic peptides with PTMs are usually enriched for enhanced coverage by LC-MS/MS. Affinity chromatography for phosphoproteomes by metal-oxide and pan-specific antibodies for lysine acetylome allow identification of tens of thousands of modification sites. Lysine methylation is a significant PTM, however, only hundreds of methylation sites were identified from available approaches. Here we report an aryl diazonium-based chemoselective strategy that enables enrichment of monomethyllysine (Kme1) peptides via covalent bond with extraordinary sensitivity. We identified more than ten thousand Kme1 peptides from diverse cell lines and mouse tissues, that implied wide lysine methylation impact on cellular processes. In addition, we found a significant amount of methyl marks that were not S-adenosyl methionine (SAM)-dependent by isotope labeling experiments. And therefore, this method paves a way to broad application in lysine methylation research and new biology discovery.

DOI: 10.1002/anie.202408564

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202408564