Persulfides, at the crossroads between hydrogen sulfide and thiols.
Dayana Benchoam1,2, Ernesto Cuevasanta1,2,3, Matías N Möller2,4
1Laboratorio de Enzimología, Instituto de Química Biológica, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay.
Essays in Biochemistry
|February 5, 2020
Summary
Persulfides (RSSH/RSS-) are reactive sulfur species formed from thiols (RSH), potentially mediating hydrogen sulfide (H2S/HS-) effects by modifying cysteines. Their unique chemistry and detection methods are key to understanding biological roles.
Area of Science:
- Biochemistry
- Chemical Biology
- Molecular Biology
Background:
- Persulfides (RSSH/RSS-) are sulfur-based molecules derived from thiols (RSH).
- Hydrogen sulfide (H2S/HS-) can influence persulfide formation pathways.
- Persulfides are implicated in the physiological effects of H2S, particularly through cysteine modification.
Purpose of the Study:
- To review the formation pathways of persulfides.
- To describe the unique biochemical properties of persulfides.
- To discuss current detection methods and biological implications of persulfides.
Main Methods:
- Literature review of persulfide formation.
- Analysis of persulfide chemical reactivity (nucleophilicity, acidity, redox potential).
- Overview of analytical techniques for persulfide detection.
Main Results:
- Persulfides are formed via multiple pathways, some involving H2S.
- Persulfides exhibit distinct chemical properties, being nucleophilic, acidic, and electrophilic.
- Persulfides are potent one-electron reductants.
Conclusions:
- Persulfides play a significant role in biological systems.
- Understanding persulfide chemistry is crucial for elucidating H2S signaling.
- Advancements in detection methods are vital for ongoing research into persulfide functions.
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