Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China.
Anal Chem. 2012 Mar 20;84(6):2908-15. doi: 10.1021/ac203467q. Epub 2012 Mar 8.
Isobaric tags have broad applications in both basic and translational research, as demonstrated by the widely used isobaric tag for relative and absolute quantitation (iTRAQ). Recent results from large-scale quantitative proteomics projects, however, indicate that protein quantification by iTRAQ is often biased in complex biological samples. Here, we report the application of another isobaric tag, deuterium isobaric amine reactive tag (DiART), for quantifying the proteome of Thermoanaerobacter tengcongensis (T. tengcongensis), a thermophilic bacterium first discovered in China. We compared the performance of DiART with iTRAQ from several different aspects, including their fragmentation mechanisms, the number of identified proteins, and the accuracy of quantification. Our results revealed that, as compared with iTRAQ, DiART yielded significantly stronger reporter ions, which did not reduce the number of identifiable peptides, but improved the signal-to-noise ratio (S/N) for quantification. Remarkably, we found that, under identical chromatography and mass spectrometry (MS) conditions, DiART exhibited less reporter ions ratio compression than iTRAQ, probably due to more reporter ions with higher intensities produced by DiART labeling. Taken together, we demonstrate that DiART is a valuable alternative of iTRAQ with enhanced performance for quantitative proteomics.
同位素质谱标签在基础研究和转化研究中都有广泛的应用，被广泛应用的相对和绝对定量同位素质谱标签（iTRAQ）就是一个很好的例子。然而，最近大规模定量蛋白质组学项目的结果表明，iTRAQ 对复杂生物样品中的蛋白质定量常常存在偏差。在这里，我们报告了另一种同位素质谱标签，氘代同位素标记的胺反应标签（DiART），用于定量鉴定中国首先发现的嗜热细菌 Thermoanaerobacter tengcongensis（T. tengcongensis）的蛋白质组。我们从多个方面比较了 DiART 与 iTRAQ 的性能，包括它们的碎裂机制、鉴定的蛋白质数量以及定量的准确性。我们的结果表明，与 iTRAQ 相比，DiART 产生了明显更强的报告离子，这并没有减少可鉴定肽的数量，反而提高了定量的信噪比（S/N）。值得注意的是，我们发现，在相同的色谱和质谱（MS）条件下，DiART 表现出比 iTRAQ 更小的报告离子比率压缩，这可能是由于 DiART 标记产生了更多强度更高的报告离子。综上所述，我们证明了 DiART 是 iTRAQ 的一种有价值的替代品，具有增强的定量蛋白质组学性能。
