Cellular proteins and thiols

Cellular proteins and thiols represent a broad and heterogeneous class of molecules characterized by the presence of reactive sulfhydryl (-SH) functional groups, which are essential for maintaining cellular redox homeostasis and structural integrity. This category includes the tripeptide glutathione (GSH), the most abundant non-protein thiol, as well as a vast array of cysteine-containing proteins that participate in redox signaling and enzymatic catalysis (PubChem, CID 124886). In pharmacology, these molecules often act as a 'sink' or non-specific site of action for electrophilic drugs, such as platinum-based chemotherapeutics and alkylating agents, which can lead to drug sequestration and the development of chemoresistance (PubMed, PMID: 11485329). While not a discrete therapeutic target, the modulation of thiol levels is a key strategy in treating oxidative stress-related conditions and heavy metal poisoning (StatPearls, NBK537183). Because this term encompasses thousands of distinct molecular species across various cellular compartments, it is considered too broad to serve as a specific canonical drug target in modern molecular pharmacology.

Other names

Sulfhydryl groupsProtein thiolsNon-protein thiolsThiol-containing moleculesCellular sulfhydryls

Drugs interact with cellular proteins and thiols primarily through covalent binding to nucleophilic sulfhydryl (-SH) groups, leading to the formation of adducts, depletion of antioxidant pools like glutathione, or the inhibition of thiol-dependent enzymes. Some agents, like N-acetylcysteine, act as precursors to replenish these thiol pools and restore redox balance.