Mass spectrometry has emerged as a core technique for protein identification and characterization because of its high sensitivity, accuracy, and speed of analysis. The most widespread strategy for studying global protein expression in biological systems employs analytical two-dimensional polyacrylamide gel electrophoresis (2D PAGE) followed by enzymatic degradation of isolated protein spots, peptide mapping, and bioinformatics searches. Using this method, thousands of proteins can be resolved in a gel and their expression quantified. However, certain types of proteins possessing important cellular functions are not easily analyzed using this strategy. These proteins include membrane, low copy number, highly basic, and very large (> 150 kDa) and small (< 10 kDa) proteins. To meet the growing need to simultaneously monitor all types of proteins in a biological system, new separation strategies have emerged that are amenable to hyphenation to mass spectrometric techniques. This article will review these new techniques and examine their usefulness in studies of protein expression.

中文翻译：

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用于通过质谱全面研究蛋白质表达的新型分离工具。

质谱法由于其高灵敏度，准确性和分析速度而已成为蛋白质鉴定和表征的核心技术。研究生物系统中全局蛋白质表达的最广泛策略是使用分析型二维聚丙烯酰胺凝胶电泳（2D PAGE），然后对分离的蛋白质斑点进行酶促降解，肽图分析和生物信息学搜索。使用这种方法，可以在凝胶中分离出数千种蛋白质，并对其表达进行定量。然而，使用这种策略不容易分析具有重要细胞功能的某些类型的蛋白质。这些蛋白质包括膜，低拷贝数，高碱性，非常大（> 150 kDa）和小的（<10 kDa）蛋白质。为了满足在生物系统中同时监测所有类型蛋白质的不断增长的需求，出现了新的分离策略，这些策略适合于质谱技术的连接。本文将回顾这些新技术，并研究它们在蛋白质表达研究中的有用性。