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Deep Top-Down Proteomics Using Capillary Zone Electrophoresis-Tandem Mass Spectrometry: Identification of 5700 Proteoforms from the Escherichia coli Proteome

ABSTRACT: We present an orthogonal multidimensional separation platform that couples size exclusion chromatography (SEC) and RPLC based protein prefractionation to CZE-MS/MS for deep top-down proteomics of Escherichia coli. The platform generated high peak capacity (∼4000) for separation of intact proteins, leading to the identification of 5700 proteoforms from the Escherichia coli proteome.

INSTRUMENT(S):

ORGANISM(S): Escherichia Coli

TISSUE(S): Cell Culture

SUBMITTER: Kun Li

LAB HEAD: Liangliang Sun

PROVIDER: PXD071282 | Pride | 2025-12-15

REPOSITORIES: Pride

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			Action	DRS
	Ecoli_SEC1_F1.raw	Raw
	Ecoli_SEC1_F1_ms2_toppic_proteoform_single.tsv	Tabular
	Ecoli_SEC1_F2.raw	Raw
	Ecoli_SEC1_F3.raw	Raw
	Ecoli_SEC1_F4.raw	Raw

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Publications

Deep Top-Down Proteomics Using Capillary Zone Electrophoresis-Tandem Mass Spectrometry: Identification of 5700 Proteoforms from the Escherichia coli Proteome.

McCool Elijah N EN Lubeckyj Rachele A RA Shen Xiaojing X Chen Daoyang D Kou Qiang Q Liu Xiaowen X Sun Liangliang L

Analytical chemistry 20180409 9

Capillary zone electrophoresis (CZE)-tandem mass spectrometry (MS/MS) has been recognized as a useful tool for top-down proteomics. However, its performance for deep top-down proteomics is still dramatically lower than widely used reversed-phase liquid chromatography (RPLC)-MS/MS. We present an orthogonal multidimensional separation platform that couples size exclusion chromatography (SEC) and RPLC based protein prefractionation to CZE-MS/MS for deep top-down proteomics of Escherichia coli. The ...[more]

PMID: 29620868

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