Predicting the Possible Physiological/Biological Utility of the Hydropersulfide Functional Group Based on Its Chemistry: Similarities Between Hydropersulfides and Selenols

Alkylsulfenyl thiocarbonates: precursors to hydropersulfides potently attenuate oxidative stress

“…In fact, this transformation has been proposed to protect protein thiols from irreversible modification during oxidative and/or electrophilic insult. 11 Consistent with this hypothesis, Greiner and co-workers demonstrated that the phosphatase and tensin homolog (PTEN) is protected from irreversible H 2 O 2 -mediated inhibition when the protein is in the PSSH form. 19 Accumulating evidence suggests that the electrophilic nature of RSSH serves to regulate redox signaling and contribute to various cellular functions.…”

“…9, 10 The chemical properties and abundance of these species suggest that RSSH play important roles in various physiological processes. 11 CysSSH can be generated via the enzymes cystathionine g-lyase (CSE) and cystathionine b-synthase (CBS), both of which utilize cystine (CysSSCys) as a substrate. 7,12 In addition, recently it has been reported that CysSSH can be synthesized by cysteinyl-tRNA synthetases (CARSs) utilizing CysSH as a substrate.…”

A Low-Crossover and Fast-Kinetics Thiolate Negolyte for Aqueous Redox Flow Batteries

“…Both the static cells and flow cells were sealed in Ar-filled glove box and tested in air. This is because the thiolate (HO-CH 2 -CH 2 -S-S -K + ) could be oxidized to HO-CH 2 -CH 2 -S-SO 2 -K + by oxygen considering the thiol (R-S-S-H) is reported to be oxidized to R-S-SO 2 H by oxidizing agents [37,38].…”

The antioxidant and oxidant properties of hydropersulfides (RSSH) and polysulfide species

“…Indeed, the –SSH group can be compared to the selenol functional group (-SeH, which denotes both the protonated and unprotonated, -Se - , species) in that -SeH has superior nucleophilicity and reducing abilities compared to the corresponding –SH containing species. In this regard, Cys-SSH and/or associated sulfurated thiol proteins (PSSH) can be considered to be ‘fleeting’ selenocysteine (Sec) and/or selenoprotein analogs [ 16 ] (note: RSSH/PSSH can be considered fleeting due to the existence of the reverse of Reaction 1 ). Moreover, the inherent reactivity of the –SSH functional group as a nucleophile and reductant has led to favorable comparisons to numerous biological protective/antioxidant systems such as ascorbate, α-tocopherol, glutathione (GSH), glutathione transferase (GST), glutaredoxin (Grx) and glutathione peroxidase (GPx) [ 17 ].…”