Dataset Information

Label-free mass spectrometry analysis of laminin with induced oxidations and chlorination’s facilitated with hypochlorous acid and myeloperoxidase treatments.

ABSTRACT: Basement membranes are specialized extracellular matrices that underlie arterial wall endothelial cells, with laminin being a key structural and biologically-active component. Hypochlorous acid (HOCl), a potent oxidizing and chlorinating agent, is formed in vivo at sites of inflammation, via the enzymatic action of myeloperoxidase (MPO), released by activated leukocytes. Murine Laminin was treated with two oxidative systems to mimic the exposure of MPO-derived HOCl in atherosclerotic condition. Sites of oxidation and chlorination on isolated laminin-111 were detected and quantified by mass spectrometry. An increased number of modifications was detected with increasing oxidant exposure. HOCl oxidised 30 (of 56 total) Met and 7 (of 24) Trp-residues and chlorinated 33 (of 99) Tyr-residues; three Tyr-residues were dichlorinated. An additional 8 Met- and 10 Trp-oxidations, 14 chlorinations, and 18 dichlorinations were detected on Tyr-residues with the MPO system when compared to reagent HOCl. These data indicate that laminin is extensively modified by MPO-derived oxidants, with structural and functional changes. These modifications, and compromised cell-matrix interactions, may promote endothelial cell dysfunction, weaken the structure of atherosclerotic lesions, and enhance lesion rupture.

INSTRUMENT(S):

ORGANISM(S): Mus Musculus (mouse)

SUBMITTER: Adelina Rogowska-Wrzesinska

LAB HEAD: Adelina Rogowska-Wrzesinska

PROVIDER: PXD022056 | Pride | 2025-11-05

REPOSITORIES: Pride

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Chlorination and oxidation of the extracellular matrix protein laminin and basement membrane extracts by hypochlorous acid and myeloperoxidase.

Nybo Tina T Dieterich Simon S Gamon Luke F LF Chuang Christine Y CY Hammer Astrid A Hoefler Gerald G Malle Ernst E Rogowska-Wrzesinska Adelina A Davies Michael J MJ

Redox biology 20181103

Basement membranes are specialized extracellular matrices that underlie arterial wall endothelial cells, with laminin being a key structural and biologically-active component. Hypochlorous acid (HOCl), a potent oxidizing and chlorinating agent, is formed in vivo at sites of inflammation via the enzymatic action of myeloperoxidase (MPO), released by activated leukocytes. Considerable data supports a role for MPO-derived oxidants in cardiovascular disease and particularly atherosclerosis. These ef ...[more]

PMID: 30476874

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			Action	DRS
	Laminin_Murine.fasta	Fasta
	Laminin_Murine_MPO.fasta	Fasta
	P03_E04-_2_.msf	Msf
	P03_E04.mgf	Mgf
	P07_E01_Progenesis-_2_.msf	Msf