Single-run mass spectrometry has enabled the detection and quantifications of E. coli proteins. A total of 2068 proteins quantified by intensity-based absolute quantification (iBAQ) Schwanhäusser et al.: (Nature. 473, 337–342, 2011) procedure were obtained with single enzyme-trypsin, without pre-fractionation, by quadruplicate long liquid chromatography runs coupled with high-resolution linear trap quadrupole (LTQ)-Orbitrap Velos mass spectrometry. The single-run of 12 h has ability to cover almost 98% of the quadruplicate LC-MS/MS runs of E. coli proteome and is therefore almost equivalent to quadruplicate LC-MS/MS runs. These quantified proteins are about 52% of the total proteins present in E. coli genome according to Uniprot database. The quantified proteins covered almost all of the proteins in folate biosynthesis. Remarkably greater part of Gene Ontology (GO) Barrell et al.: (Nucleic Acids Res. 37, D396–D403, 2009), Ashburner et al.: (Nat. Genet. 25, 25–29, 2000) annotations, signaling pathways along with protein-protein interactions were covered. Some of the important biological processes-cell cycle, DNA repair, ion transport, ubiquinone biosynthetic process, pseudouridine synthesis, peptidoglycan biosynthetic process, RNA processing, and translation-revealed protein-protein interaction network generated by Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) Jensen, et al.:(Nucleic Acids Res 37, D412-D126, 2009) database. Therefore, to achieve the saturation point of detection of maximum number of proteins in single LC-MS/MS run, 12-h liquid chromatography gradient is appropriate.

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单次运行质谱分析法能够检测和定量大肠杆菌蛋白质。总共2068种蛋白质的定量通过基于强度的绝对定量（iBAQ）Schwanhäusser等人：（性质。473，337-342，2011）用单个酶，胰蛋白酶获得的程序，而无需预分级，由一式四份长液相色谱与高分辨率线性阱四极杆（LTQ）-Orbitrap Velos质谱联用。12小时的单次运行能够覆盖几乎98％的大肠杆菌蛋白质组四次LC-MS / MS运行，因此几乎等同于四次LC-MS / MS运行。这些量化的蛋白质约占大肠杆菌中蛋白质总数的52％根据Uniprot数据库的基因组。定量的蛋白质几乎涵盖了叶酸生物合成中的所有蛋白质。基因本体论（GO）的显着更大的部分巴雷尔等人：（核酸研究37，D396-D403，2009年），阿什伯纳等人：（NAT。遗传学。25，25-29，2000）注释，信号传导途径以及蛋白质间相互作用。搜索工具检索相互作用基因/蛋白质（STRING）Jensen等人：（Nucleic Acids Res 37，D412-D126，2009）数据库。因此，为了在单个LC-MS / MS运行中达到最大蛋白质检测数量的饱和点，适合使用12小时液相色谱梯度。

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