Related Experiment Video
Updated: Feb 13, 2026

Development and Identification of a Novel Subpopulation of Human Neutrophil-derived Giant Phagocytes In Vitro
Published on: January 25, 2017
Neutrophil-generated HOCl leads to non-specific thiol oxidation in phagocytized bacteria
Adriana Degrossoli1, Alexandra Müller1, Kaibo Xie1
1Institute for Biochemistry and Pathobiochemistry - Microbial Biochemistry, Ruhr-Universität Bochum, Bochum, Germany.
Abstract:
Phagocytic immune cells kill pathogens in the phagolysosomal compartment with a cocktail of antimicrobial agents. Chief among them are reactive species produced in the so-called oxidative burst. Here, we show that bacteria exposed to a neutrophil-like cell line experience a rapid and massive oxidation of cytosolic thiols. Using roGFP2-based fusion probes, we could show that this massive breakdown of the thiol redox homeostasis was dependent on phagocytosis, presence of NADPH oxidase and ultimately myeloperoxidase. Interestingly, the redox-mediated fluorescence change in bacteria expressing a glutathione-specific Grx1-roGFP2 fusion protein or an unfused roGFP2 showed highly similar reaction kinetics to the ones observed with roGFP2-Orp1, under all conditions tested. We recently observed such an indiscriminate oxidation of roGFP2-based fusion probes by HOCl with fast kinetics in vitro. In line with these observations, abating HOCl production in immune cells with a myeloperoxidase inhibitor significantly attenuated the oxidation of all three probes in bacteria.
Related Concept Videos
Oxidation Numbers
Preparation and Reactions of Thiols
Oxidation-Reduction Reactions
Structure and Nomenclature of Thiols and Sulfides
Pyruvate Oxidation
First, the enzyme pyruvate dehydrogenase removes the carboxyl group from pyruvate and releases it as carbon dioxide. The stripped molecule is then oxidized and releases electrons, which are then picked up by NAD+...
Phase-lead and Phase-lag Controllers

