BiomolecularMass Spectrometry and Proteomics Group, Bijvoet Centre for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences,Utrecht University, CH Utrecht, The Netherlands.
J Proteomics. 2011 Sep 6;74(10):2204-9. doi: 10.1016/j.jprot.2011.04.022. Epub 2011 May 15.
High-resolution mass spectrometry and the use of stable isotopes have greatly improved our ability to quantify proteomes. Typically, the relative abundance of peptides is estimated by identifying the isotopic clusters and by comparing the peak intensities of peptide pairs. However, when the mass shift between the labeled peptides is small, there can be the possibility for overlap of the isotopic clusters which will hamper quantification accuracy with a typical upwards bias for the heavier peptide. Here, we investigated the impact of the overlapping peak issue with respect to dimethyl based quantification and we confirmed there can be need for correction. In addition, we present a tool that can correct overlapping issues when they arise which is based on modeling isotopic distributions. We demonstrate that our approach leads to improved accuracy and precision of protein quantification.
高分辨率质谱和稳定同位素的使用极大地提高了我们定量蛋白质组的能力。通常，通过鉴定同位素簇并比较肽对的峰强度来估计肽的相对丰度。然而，当标记肽之间的质量位移较小时，可能会出现同位素簇重叠的情况，这将对较重肽的定量准确性造成典型的向上偏差。在这里，我们研究了重叠峰问题对基于二甲基的定量的影响，并证实可能需要进行校正。此外，我们还提出了一种在出现重叠问题时可以进行校正的工具，该工具基于对同位素分布的建模。我们证明，我们的方法可以提高蛋白质定量的准确性和精密度。
