Dataset Information

Dimethylthiourea as a Quencher in Hydroxyl Radical Protein Footprinting Experiments

ABSTRACT: Hydroxyl radical protein footprinting (HRPF) is a mass spectrometry (MS)-based method for studying protein structures, interactions, conformations, and folding. We evaluated dimethylthiourea (DMTU) as a replacement for catalase in quenching HRPF reactions. We observed that the DMTU is highly effective at quenching HRPF oxidation. DMTU does not cause background protein issues like catalase, resulting in an increased number of protein identifications from complex mixtures.

INSTRUMENT(S):

ORGANISM(S): Escherichia Coli

SUBMITTER: Sandeep Misra

LAB HEAD: Joshua Sharp

PROVIDER: PXD046435 | Pride | 2025-09-12

REPOSITORIES: Pride

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Dataset's files

Source:

			Action	DRS
	08-19-2022-FPOP-Ecoli-Catalase-1.raw	Raw
	08-19-2022-FPOP-Ecoli-Catalase-2.raw	Raw
	08-19-2022-FPOP-Ecoli-Catalase-3.raw	Raw
	08-19-2022-FPOP-Ecoli-DMTU-1.raw	Raw
	08-19-2022-FPOP-Ecoli-DMTU-2.raw	Raw

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Publications

Dimethylthiourea as a Quencher in Hydroxyl Radical Protein Footprinting Experiments.

Shami Anter A AA Misra Sandeep K SK Jones Lisa M LM Sharp Joshua S JS

Journal of the American Society for Mass Spectrometry 20231116 12

Hydroxyl radical protein footprinting (HRPF) is a mass-spectrometry-based method for studying protein structures, interactions, conformations, and folding. This method is based on the irreversible labeling of solvent-exposed amino acid side chains by hydroxyl radicals. While catalase is commonly used as a quencher after the labeling of a protein by the hydroxyl radicals to efficiently remove the remaining hydrogen peroxide, it has some disadvantages. Catalase quenching adds a relatively high amo ...[more]

PMID: 37971787

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