Proteome-wide Mapping of Cysteine Persulfidation in Deep-Sea Hyperthermophilic Archaea

Protein persulfidation, a primary post-translational modification mediated by the gaseous signaling molecule hydrogen sulfide (H 2 S), regulates diverse physiological processes in eukaryotes and bacteria. However, its existence and functional roles in archaea, the third domain of life, remain completely unexplored. Here, we investigate this in the deep-sea hyperthermophilic archaeon Thermococcus aciditolerans SY113, which thrives in sulfur rich hydrothermal vents and endogenously produces substantial H 2 S. Our profiling not only delineated the unique reactivity landscape of these modifications but also enabled quantitative analysis of its dynamic regulation by H 2 S. A total of 204 persulfidation sites on 171 proteins were identified, over 65% of which were dynamically regulated by H 2 S. Further functional analysis suggests that persulfidation represents an ancient and conserved regulatory mechanism in primordial life including the regulation of catalytic activity, maintenance of protein conformation, and mediation of protein-protein interactions. Our findings provide a valuable dataset and theoretical foundation for understanding the role of persulfidation in the physiological regulation of deep-sea hyperthermophilic archaea.