Relative quantification of sulfenic acids in plasma proteins using differential labelling and mass spectrometry coupled with 473 nm photo-dissociation analysis : A multiplexed approach applied to an Alzheimer's disease cohort

Copyright © 2022 Elsevier B.V. All rights reserved..

Cysteine (Cys) is subject to a variety of reversible post-translational modifications such as formation of sulfenic acid (Cys-SOH). If this modification is often involved in normal biological activities, it can also be the result of oxidative damage. Indeed, oxidative stress yields abnormal cysteine oxidations that affect protein function and structure and can lead to neurodegenerative diseases. In a context of population ageing, validation of novel biomarkers for detection of neurodegenerative diseases is important. However, Cys-SOH proteins investigation in large human cohorts is challenging due to their low abundance and lability under endogenous conditions. To improve the detection specificity towards the oxidized protein subpopulation, we developed a method that makes use of a mass spectrometer coupled with visible laser induced dissociation (LID) to add a stringent optical specificity to the mass selectivity. Since peptides do not naturally absorb in the visible range, this approach relies on the proper chemical derivatization of Cys-SOH with a chromophore functionalized with a cyclohexanedione. To compensate for the significant variability in total protein expression within the samples and any experimental bias, a normalizing strategy using free thiol (Cys-SH) cysteine peptides derivatized with a maleimide chromophore as internal references was used. Thanks to the differential tagging, oxidative ratios were then obtained for 69 Cys-containing peptides from 19 proteins tracked by parallel reaction monitoring (PRM) LID, in a cohort of 49 human plasma samples from Alzheimer disease (AD) patients. A statistical analysis indicated that, for the proteins monitored, the Cys oxidative ratio does not correlate with the diagnosis of AD. Nevertheless, the PRM-LID method allows the unbiased, sensitive and robust relative quantification of Cys oxidation within cohorts of samples.

Medienart:

E-Artikel

Erscheinungsjahr:

2022

Erschienen:

2022

Enthalten in:

Zur Gesamtaufnahme - volume:250

Enthalten in:

Talanta - 250(2022) vom: 01. Dez., Seite 123745

Sprache:

Englisch

Beteiligte Personen:

Guillaubez, Jean-Valery [VerfasserIn]
Pitrat, Delphine [VerfasserIn]
Bretonnière, Yann [VerfasserIn]
Lemoine, Jérôme [VerfasserIn]
Girod, Marion [VerfasserIn]

Links:

Volltext

Themen:

Blood Proteins
Cysteine
Cysteine oxidation
Cysteinesulfenic acid
Differential chromophore derivatization
FB8KIA847T
Journal Article
K848JZ4886
Laser induced dissociation
Maleimides
Mass spectrometry
Peptides
Sulfenic Acids
Sulfhydryl Compounds

Anmerkungen:

Date Completed 28.09.2022

Date Revised 28.09.2022

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1016/j.talanta.2022.123745

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM343901951