Cellular proteins with sulfhydryl groups

Cellular proteins with sulfhydryl groups refer to the diverse array of proteins that contain cysteine residues with reactive thiol (-SH) moieties. These groups play a fundamental role in cellular biology, participating in the formation of disulfide bridges for protein stability, acting as nucleophiles in enzymatic catalysis, and serving as key components of redox signaling pathways (StatPearls, 2023). In a clinical context, these sulfhydryl groups are significant as the primary sites of toxicity for heavy metals like mercury, lead, and arsenic, which form stable mercaptides that deactivate essential enzymes (NIH, 2022). Therapeutic strategies targeting these groups typically involve the use of chelating agents, such as dimercaprol or succimer, which possess their own sulfhydryl groups to compete for and sequester toxic metal ions (PubChem, 2024). Because sulfhydryl groups are ubiquitous across the proteome, targeting them lacks molecular specificity, often leading to broad physiological impacts and potential side effects related to the disruption of normal redox homeostasis.

Other names

Protein thiolsCysteine sulfhydryl groupsProtein-bound SH groupsReactive protein thiols

Chelation of metal ions to prevent binding to protein thiols; covalent modification of cysteine residues by electrophilic agents.