FOM-Institute for Atomic and Molecular Physics, Science Park 104, 1098 XG Amsterdam, The Netherlands.
J Proteomics. 2011 Jun 10;74(7):993-1001. doi: 10.1016/j.jprot.2011.02.009. Epub 2011 Feb 17.
Secondary Ion Mass Spectrometry (SIMS) is a well established method for sensitive surface atomic and molecular analysis. Protein analysis with conventional SIMS has been attempted numerous times; however it delivers exclusively fragment peaks assigned to α-amino acids or immonium ions. In this paper we report experiments where direct sequence information could be measured thanks to a combination of HPLC separation with matrix enhanced SIMS (ME-SIMS) on tryptic digests of intact proteins. We employ peptide mass fingerprinting (PMF) and protein identification through the detection of HPLC-separated digests of Savinase (Sav.) and bovine serum albumin (BSA), followed by MASCOT search. This is the first time that the possibility of full protein identification using LC-ME-SIMS is demonstrated in a classic proteomics workflow and that a 69kDa protein is identified with SIMS. These results demonstrate both the relevance and the potential of LC-ME-SIMS in future high resolution proteomics studies.
二次离子质谱（SIMS）是一种成熟的用于灵敏的表面原子和分子分析的方法。常规 SIMS 已被多次尝试用于蛋白质分析，但只能提供分配给α-氨基酸或亚氨离子的碎片峰。在本文中，我们报告了通过高效液相色谱分离与基质增强 SIMS（ME-SIMS）相结合的实验，直接测量完整蛋白质的胰蛋白酶消化物的序列信息。我们采用肽质量指纹图谱（PMF）和通过 Savinase（Sav.）和牛血清白蛋白（BSA）的 HPLC 分离消化物的检测进行蛋白质鉴定，然后进行 Mascot 搜索。这是首次在经典蛋白质组学工作流程中证明使用 LC-ME-SIMS 进行完整蛋白质鉴定的可能性，并且使用 SIMS 鉴定了 69kDa 蛋白质。这些结果证明了 LC-ME-SIMS 在未来高分辨率蛋白质组学研究中的相关性和潜力。
