Multiple cysteine-containing cellular proteins

Multiple cysteine-containing cellular proteins refers to a broad and heterogeneous group of proteins and enzymes characterized by the presence of reactive thiol (-SH) groups on their cysteine residues. This collective target is not a single molecular entity but a functional class of proteins that are susceptible to modification by electrophilic agents, heavy metals, and redox-active compounds (NIH, 2017). These proteins play critical roles in maintaining the cellular thiolstat and redox homeostasis, and their modification can lead to the inhibition of essential enzymes such as thioredoxin reductase, alteration of protein conformation, or the triggering of apoptotic signaling pathways (MDPI, 2017). Drugs like arsenic trioxide and ebselen, as well as toxicants like methylmercury, exert their biological effects by covalently binding to these cysteine residues (PubMed, 2010). While this multi-target interaction is exploited for therapeutic purposes in treating certain cancers and infections, the non-selective nature of these bindings often results in significant safety concerns, including systemic toxicity and oxidative stress (NIH, 2022).

Other names

Thiol-containing proteinsSulfhydryl-containing proteinsCysteine-rich proteinsCellular thiolstatRedox-sensitive proteins

Covalent modification of cysteine thiol groups, leading to enzyme inhibition, conformational changes, and disruption of cellular redox homeostasis.