The biological functions of protein S-sulfhydration in eukaryotes and the ever-increasing understanding of its effects on bacteria.

As a critical endogenous signaling molecule, hydrogen sulfide may induce reversible post-translational modifications on cysteine residues of proteins, generating a persulfide bond known as S-sulfhydration. A systemic overview of the biofunctions of S-sulfhydration will equip us better to characterize its regulatory roles in antioxidant defense, inflammatory response, and cell fate, as well as its pathological mechanisms related to cardiovascular, neurological, and multiple organ diseases, etc. Nevertheless, the understanding of S-sulfhydration is mostly built on mammalian cells and animal models. We subsequently summarized the mediation effects of this specific post-transcriptional modification on physiological processes and virulence in bacteria. The high-sensitivity and high-throughput detection technologies are required for studying the signal transduction mechanism of HS and protein S-sulfhydration modification. Herein, we reviewed the establishment and development of different approaches to assess S-sulfhydration, including the biotin-switch method, modified biotin-switch method, alkylation-based cysteine-labelled assay, and Tag-switch method. Finally, we discussed the limitations of the impacts of S-sulfhydration in pathogens-host interactions and envisaged the challenges to design drugs and antibiotics targeting the S-sulfhydrated proteins in the host or pathogens.