Monitoring of protein thiol-oxidation in S.aureus USA300 under hypochlorite stress using OxICAT approach.

During infections, S. aureus has to cope with the oxidative burst of activated macrophages and neutrophils, including reactive oxygen and nitrogen species (RNS, ROS) and the strong oxidant hypochloric acid. We aimed to understand the global thiol-redox state in the major pathogen S. aureus and discover new NaOCl-sensitive proteins driven by thiol-switches. Thus, we performed a quantitative redox proteomics approach based on OxICAT and analyzed the percentages of thiol-oxidation levels in S.aureus before and after sub-lethal doses of 150 µM NaOCl stress. In parallel, we searched for protein S-bacillithiolation.