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Updated: Jan 13, 2026

Resin-Assisted Capture Coupled with Isobaric Tandem Mass Tag Labeling for Multiplexed Quantification of Protein Thiol Oxidation
Published on: June 21, 2021
Acid-catalyzed esterification and biotin/fluorescent labeling of glutathione polysulfides based on stability under
Masana Yazaki1, Yaozhuo Zhang1, Lin Zhou1
1Department of Bioscience and Biotechnology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, Fukuoka, 819-0395, Japan. arisawa@agr.kyushu-u.ac.jp.
Abstract:
Glutathione polysulfides GSSSG and GSSSSG are stable in water up to 80 °C and below pH 9. Their carboxyl groups can be efficiently esterified with TMSCl in alcohols, reacting first at glycine, then glutamic acid. The resulting 3-butyne-1-yl esters allow Cu-catalyzed labeling (e.g., biotin, fluorophore) and can be hydrolyzed by esterases.
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