persulfidome

Persulfidome refers to the complete set of persulfidated proteins and cysteine residues within a biological system at a given time. Persulfidation, or S-sulfhydration, is a post-translational modification in which a cysteine thiol (-SH) is converted to a persulfide (-SSH), often as a result of hydrogen sulfide (H2S) signaling or redox processes. The persulfidome is dynamic and context-dependent, varying with cell type, physiological state, and exposure to oxidative or nitrosative stress, as well as to H2S-donor compounds.

Proteomic approaches identify and quantify components of the persulfidome by detecting persulfidated cysteines. Common workflows involve blocking free thiols, selectively reducing persulfides, labeling the resulting thiols, and enriching modified peptides for analysis by mass spectrometry. These methods yield lists of persulfidated proteins and modified sites, and can be coupled with quantitative strategies to compare conditions such as stress, disease, or treatment.

Biological significance and scope are active areas of study. Persulfidation can regulate enzyme activity, protein stability, and signaling pathways, with notable relevance to redox biology and mitochondrial function. The persulfidome is studied to understand hydrogen sulfide biology and its role in cellular regulation. Limitations include methodological challenges, potential artifacts, and incomplete coverage of low-abundance proteins; ongoing efforts aim to standardize techniques and interpretation, enabling more comprehensive and comparable persulfidome analyses.