Redox-Active Thiol Group

A redox-active thiol group refers to a sulfur-containing functional group (–SH), typically found in the amino acid cysteine, that can undergo reversible oxidation and reduction reactions. These groups are highly reactive due to the nucleophilic nature of sulfur and play critical roles in cellular redox signaling, enzymatic catalysis, protein structure stabilization, and metal ion coordination. They act as sensors and mediators of oxidative and nitrosative stress and are susceptible to modifications such as sulfenylation, disulfide bond formation, S-thiolation, and S-nitrosylation. Dysregulation or irreversible modification leads to loss-of-function or gain-of-toxic-function effects implicated in various diseases.

Other names

Thiol groupSulfhydryl group (-SH)Cysteine thiolRedox-sensitive cysteine

Modulation of redox state; Direct modification of cysteine residues; Disulfide bond formation/reduction; S-nitrosylation/denitrosylation