Sitnikov Dmitri, Hunter Joanna M, Hayward Clive, Eng Kevin, Migneault Isabelle, Tessier Sylvain, Opiteck Gregory J, Kearney Paul
Caprion Proteomics, Montreal, Quebec, Canada.
J Am Soc Mass Spectrom. 2007 Sep;18(9):1638-45. doi: 10.1016/j.jasms.2007.06.003. Epub 2007 Jun 19.
Chromatographic protein and peptide separation technologies enable comprehensive proteomic analysis of plasma and other complex biological samples by mass spectrometry. However, as the number of separations and/or fractions increases, so does the number of peptides split across fraction boundaries. Irreproducibility of peptide chromatographic separation results in peptides on or near the boundary moving partially or entirely into adjacent fractions. Peptide shifting across fraction boundaries increases the variability of measured peptide abundance, and so there is a trade-off between proteomic comprehensiveness using separation technologies and accurate quantitative proteomic measurements. In this paper, a method for detecting and correcting split peptides, called Peptide Shifter, is introduced and evaluated. An essential component of Peptide Shifter is a global peptide expression profile analysis that allows the inference of the underlying peptide shift pattern without the use of peptide labeling or internal standards. A controlled proteomic analysis of plasma samples demonstrates a 34% decrease in peptide intensity variability after the application of Peptide Shifter.
色谱蛋白质和肽分离技术能够通过质谱对血浆及其他复杂生物样品进行全面的蛋白质组分析。然而，随着分离次数和/或馏分数量的增加，跨馏分边界拆分的肽数量也会增加。肽色谱分离的不可重复性导致边界上或附近的肽部分或全部转移到相邻馏分中。肽跨馏分边界的移动增加了测量肽丰度的变异性，因此在使用分离技术的蛋白质组全面性和准确的定量蛋白质组测量之间存在权衡。本文介绍并评估了一种检测和校正拆分肽的方法，称为肽移位器（Peptide Shifter）。肽移位器的一个重要组成部分是全局肽表达谱分析，它允许在不使用肽标记或内标的情况下推断潜在的肽移位模式。对血浆样品进行的对照蛋白质组分析表明，应用肽移位器后肽强度变异性降低了34%。
