Biological Sciences Division and Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, Washington 99352, United States.
Anal Chem. 2012 Mar 20;84(6):2862-7. doi: 10.1021/ac203394r. Epub 2012 Mar 2.
Sodium dodecyl sulfate (SDS) is one of the most popular laboratory reagents used for biological sample extraction; however, the presence of this reagent in samples challenges LC-MS-based proteomics analyses because it can interfere with reversed-phase LC separations and electrospray ionization. This study reports a simple SDS-assisted proteomics sample preparation method facilitated by a novel peptide-level SDS removal step. In an initial demonstration, SDS was effectively (>99.9%) removed from peptide samples through ion substitution-mediated DS(-) precipitation using potassium chloride (KCl), and excellent peptide recovery (>95%) was observed for <20 μg of peptides. Further experiments demonstrated the compatibility of this protocol with LC-MS/MS analyses. The resulting proteome coverage obtained for both mammalian tissues and bacterial samples was comparable to or better than that obtained for the same sample types prepared using standard proteomics preparation methods and analyzed using LC-MS/MS. These results suggest the SDS-assisted protocol is a practical, simple, and broadly applicable proteomics sample processing method, which can be particularly useful when dealing with samples difficult to solubilize by other methods.
十二烷基硫酸钠（SDS）是一种常用于生物样品提取的实验室试剂；然而，由于其在样品中存在，会干扰反相 LC 分离和电喷雾电离，因此它会对基于 LC-MS 的蛋白质组学分析造成挑战。本研究报告了一种简单的 SDS 辅助蛋白质组学样品制备方法，该方法通过新颖的肽级 SDS 去除步骤得以实现。在初步验证中，通过使用氯化钾（KCl）进行离子取代介导的 DS(-)沉淀，有效地（>99.9%）从肽样品中去除 SDS，并且观察到<20μg 的肽的回收率>95%。进一步的实验表明，该方案与 LC-MS/MS 分析兼容。对于哺乳动物组织和细菌样品，使用该方案获得的蛋白质组覆盖率与使用标准蛋白质组学制备方法制备并使用 LC-MS/MS 分析的相同样品类型获得的覆盖率相当或更好。这些结果表明 SDS 辅助方案是一种实用、简单且广泛适用的蛋白质组学样品处理方法，当遇到其他方法难以溶解的样品时，该方法尤其有用。
