Dataset Information

Identifying subcellular structure components in Escherichia Coli by crosslinking and SEC-MS

ABSTRACT: Cells are comprised of a broad spectrum of structures that compartmentalize biochemical and signaling mechanisms. These structures can be comprised of many biomolecules, but especially lipids, proteins, and nucleic acids. Options are limited to quantify or discover new subcellular structures. We explored a proteomics approach to this challenge chemical crosslinking followed by size-exclusion chromatography and mass spectrometry (SEC-MS). Formaldehyde crosslinking was used to preserve the weak molecular interactions responsible for many protein and nucleic acid assemblies. We demonstrate that when expressed ectopically in E. Coli, large structures of a known assembly protein, FUS, can be detected through SEC-MS. We then show that E. Coli proteins are enriched in particles of large or medium size due to formaldehyde crosslinking. Last, analysis of SEC-MS showed evidence of previously characterized E. Coli protein assemblies and condensates, as well as potentially novel associations of prokaryote metabolism with large sub-cellular bodies. We propose this unbiased method can be used to stimulate or supplement targeted methods for discovery of new cellular bodies in a wide range of cell types.

INSTRUMENT(S):

ORGANISM(S): Escherichia Coli

SUBMITTER: Paul Langlais

LAB HEAD: Jacob Schwartz

PROVIDER: PXD054099 | Pride | 2026-05-25

REPOSITORIES: Pride

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			Action	DRS
	20210212_R2D2_4507_1.raw	Raw
	20210212_R2D2_4507_1.raw__F009423_.mzid.gz	Mzid
	20210212_R2D2_4507_1.raw__F009423_.mzid_20210212_R2D2_4507_1.raw__F009423_.MGF	Mzid
	20210212_R2D2_4507_10.raw	Raw
	20210212_R2D2_4507_10.raw__F009432_.mzid.gz	Mzid

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Identifying Subcellular Structure Components in Escherichia Coli by Crosslinking and SEC-MS.

Victor Rachel A RA Lipinski Austin A Langlais Paul R PR Schwartz Jacob C JC

Proteomics 20260121 5

Cells are comprised of a broad spectrum of structures that compartmentalize biochemical and signaling mechanisms. These structures can be comprised of many biomolecules, but especially lipids, proteins, and nucleic acids. Techniques are limited to quantify or discover new subcellular structures. We explored whether a proteomics approach using chemical crosslinking followed by size-exclusion chromatography and mass spectrometry (SEC-MS) of whole cell lysates can address this challenge. Formaldehy ...[more]

PMID: 41566810

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