Bovine sarcoplasmic sub-proteome was studied through a straightforward gel-free pipeline supported by liquid isoelectric focusing (OFFGEL) protein fractionation coupled to liquid chromatography-mass spectrometry (LC-MS) analysis. Full-MS and data-dependent MS/MS analyses were simultaneously performed by a conventional three-dimensional ion-trap addressing targeted quantitative and untargeted qualitative research, respectively. There were unambiguously identified 47 proteins distributed along 12 OFFGEL fractions assayed. Regarding intermediate- and high-abundant peptides, bulky quantitative data processing performed by MZmine 2 freeware yielded a satisfactory linearity and coefficient of variation with r2 in the 0.95-0.99 range and about 25%, respectively. Up to 41 peptides from 20 identified proteins were relatively quantified throughout OFFGEL fractions. This reliable, flexible and affordable gel-free proteomic approach could be readily implemented by industry to improve quality assessment of protein-based food products.

中文翻译：

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通过液体等电聚焦 (OFFGEL) 和质谱分析辅助研究牛肉蛋白质组的简单无凝胶蛋白质组学管道

通过由液体等电聚焦 (OFFGEL) 蛋白质分级结合液相色谱-质谱 (LC-MS) 分析支持的简单无凝胶管道研究牛肌浆亚蛋白质组。完整的 MS 和数据相关的 MS/MS 分析是通过传统的三维离子阱同时进行的，分别针对目标定量和非目标定性研究。有明确鉴定的 47 种蛋白质分布在 12 个所测定的 OFFGEL 级分中。关于中丰度和高丰度肽，由 MZmine 2 免费软件执行的大量定量数据处理产生了令人满意的线性和变异系数，r2 分别在 0.95-0.99 范围内和约 25%。在整个 OFFGEL 级分中，对来自 20 种已鉴定蛋白质的多达 41 种肽进行了相对定量。这种可靠、灵活且经济实惠的无凝胶蛋白质组学方法可以很容易地被工业实施，以改善基于蛋白质的食品的质量评估。