Persulfides: current knowledge and challenges in chemistry and chemical biology.

Recent studies conducted in hydrogen sulfide (H2S) signaling have revealed potential importance of persulfides (RSSH) in redox biology. The inherent instability of RSSH makes these species difficult to study and sometimes controversial results are reported. In this review article we summarize known knowledge about both small molecule persulfides and protein persulfides. Their fundamental physical and chemical properties such as preparation/formation and reactivity are discussed. The biological implications of persulfides and their detection methods are also discussed.