Modern Research Center for Traditional Chinese Medicine, School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing, 100029, China.
State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Taipa, 999078, Macao.
Anal Chim Acta. 2019 Sep 3;1069:89-97. doi: 10.1016/j.aca.2019.04.013. Epub 2019 Apr 11.
Either widely targeted metabolomics or quantitative proteomics usually requires unique analytical platform. However, cross-platform omics studies entail higher levels of complexity and uncertainty, and result in a significant obstacle for high throughput assay as well. It is thereby urgent to pursue an integrative approach being capable of merging these two omics terms, namely widely targeted bi-omics. As an eligible analytical tool for large-scale targeted metabolomics, reversed phase liquid chromatography-hydrophilic interaction liquid chromatography-tailored selected reaction monitoring (RPLC-HILIC-tailored SRM) was deployed here to further receive the tryptic peptides as the analytes. Comparative evaluation of metabolites and tryptic peptides, 101 ones in total, between HepG2 and SK-Hep1 cells was conducted as a proof-of-concept. All analytes, regardless of metabolites or peptides, exhibited satisfactory chromatographic behaviors on RPLC-HILIC. Quantitative MS parameters, such as SRM transitions and collision energies (CEs), of either tryptic peptides or metabolites were online optimized in a standard compound-independent manner. It was worthwhile to mention that the signal responses of the peptides-of-choice generated by the optimized CEs were significantly superior to those values suggested by Skyline software. Calibration curves of both metabolites and peptides were constructed by serially diluting a so-called universal metabolome standard (UMS) sample. The quasi-content of each peptide or metabolite was gained according to applying those regressive calibration curves. After subjecting the quasi-content dataset into SIMCA-P software, significant differences took place between the two hepatic cell lines, and not only metabolites but tryptic peptides contributed to the discrimination. Above all, RPLC-HILIC-tailored SRM offered a promising choice towards widely targeted bi-omics attributing to the advantage of simultaneous monitoring metabolites and tryptic peptides.
要么广泛靶向代谢组学，要么定量蛋白质组学通常需要独特的分析平台。然而，跨平台组学研究需要更高水平的复杂性和不确定性，并且对高通量分析也会产生显著的障碍。因此，迫切需要寻求一种能够融合这两种组学术语的综合方法，即广泛靶向双组学。作为一种适用于大规模靶向代谢组学的分析工具，反相液相色谱-亲水相互作用液相色谱-定制选择反应监测（RPLC-HILIC-定制 SRM）被用于进一步接收作为分析物的胰蛋白酶肽。作为概念验证，对 HepG2 和 SK-Hep1 细胞中的代谢物和胰蛋白酶肽 101 种进行了比较评估。所有分析物，无论是代谢物还是肽，在 RPLC-HILIC 上均表现出令人满意的色谱行为。无论是胰蛋白酶肽还是代谢物的定量 MS 参数，如 SRM 跃迁和碰撞能（CE），均以标准化合物独立的方式在线优化。值得一提的是，通过优化 CE 生成的所选肽的信号响应明显优于 Skyline 软件建议的值。通过连续稀释所谓的通用代谢物标准（UMS）样品来构建代谢物和肽的校准曲线。根据应用这些回归校准曲线，获得每个肽或代谢物的准含量。将准含量数据集输入 SIMCA-P 软件后，两种肝细胞系之间存在显著差异，不仅代谢物而且胰蛋白酶肽也有助于区分。总之，RPLC-HILIC-定制 SRM 为广泛靶向双组学提供了一个有前途的选择，因为它具有同时监测代谢物和胰蛋白酶肽的优势。
