Reactive cysteine persulfides and S-polythiolation regulate oxidative stress and redox signaling

Abstract

Using methodology developed herein, it is found that reactive persulfides and polysulfides are formed endogenously from both small molecule species and proteins in high amounts in mammalian cells and tissues. These reactive sulfur species were biosynthesized by two major sulfurtransferases: cystathionine β-synthase and cystathionine γ-lyase. Quantitation of these species indicates that high concentrations of glutathione persulfide (perhydropersulfide >100 μM) and other cysteine persulfide and polysulfide derivatives in peptides/proteins were endogenously produced and maintained in the plasma, cells, and tissues of mammals (rodent and human). It is expected that persulfides are especially nucleophilic and reducing. This view was found to be the case, because they quickly react with H 2 O 2 and a recently described biologically generated electrophile 8-nitroguanosine 3′,5′-cyclic monophosphate. These results indicate that persulfides are potentially important signaling/effector species, and because H 2 S can be generated from persulfide degradation, much of the reported biological activity associated with H 2 S may actually be that of persulfides. That is, H 2 S may act primarily as a marker for the biologically active of persulfide species.thiol redox | hydrogen sulfide | electrophilic signaling | polysulfidomics H ydrogen sulfide (H 2 S) has been suggested to be an endogenous small molecule signaling species (1) by unknown mechanisms. Our laboratory recently showed that the presence of hydrogen sulfide anion (HS − ) may be responsible for the regulation and metabolism of various important electrophilic species [e.g., 8-nitroguanosine 3′,5′-cyclic GMP (8-nitro-cGMP)] (2). However, these studies also indicated that reactive intermediates other than HS − likely react with the electrophiles of interest. These previous studies alluded to the generation of a more reactive sulfur species capable of reacting with electrophiles, such as 8-nitro-cGMP. As reported herein, it was determined that reactive sulfur intermediates, such as hydropersulfides (RSSH) and polysulfides [RS(S) n H and RS(S) n SR], are formed in appreciable amounts during sulfur amino acid metabolism and possess important chemical and biological properties. Some of these sulfide species have long been known as sulfane sulfur compounds, which were suggested to exist endogenously in mammalian systems (1,(3)(4)(5). Reports also indicated that a hydropersulfide moiety with the general molecular formula RSSH may be formed on specific protein cysteine (Cys) residues, most typically of sulfur-transferring enzymes (i.e., sulfurtransferases) during enzymatic reactions (1, 5). Although such persulfide chemical reactivity is thought to be involved in the catalytic activity of particular enzymes (e.g., rhodanese, Cys desulfurases, and sulfide:quinone oxidoreductase) (6, 7), the more general physiological function and occurrence of Cys persulfides (CysSSH) and related species in cells and tissues, especially mammals, were unclear. Moreover, the exact chemical nature ...

Examining the reaction of NO and H 2 S and the possible cross-talk between the two signaling pathways

“…This is interesting because polysulfide formation is also a result of H 2 S and NO reactivity, indicating that polysulfides may not only be a product of reaction, but they may also be an intermediate along the reaction pathway. Others have also observed similar results when studying sulfide reactivity, leading to the notion that oxidized sulfide species, such as polysulfides, may be important species in reactions involving sulfides, and therefore must be considered in such chemistry (11).…”

Near-Infrared Fluorescent Probe for Imaging Mitochondrial Hydrogen Polysulfides in Living Cells and in Vivo

“…[9][10][11]42 Since there exists a dynamic distribution among hydrogen polysulfide species, 12−16 we then evaluated the roles of the enzyme CSE in hydrogen polysulfides generation. Another enzyme cystathionine β-synthase (CBS) was also tested.…”

Biological hydropersulfides and related polysulfides – a new concept and perspective in redox biology

“…These enzymes appear to be responsible for at least a portion of the Cys‐SSH found in cells since, for example, CSE knock out cells were significantly lower in intracellular hydropersulfides (and polysulfides) and CSE overexpressing cells possessed high levels 27. Previous work by Sen and coworkers using an improved maleimide‐based assay also showed that CSE‐delete mice lacked the ability to form hydropersulfides on the p65 subunit of NF‐κβ 39, affecting activity and Mustafa et al .…”