Protein cysteine residue oxidation by reactive oxygen species

Cysteine residues within proteins are central sensors and transmitters of redox changes due to their highly reactive thiol (-SH) group[1][5][6]. Exposure to reactive oxygen species such as hydrogen peroxide, superoxide, and related oxidants results in various oxidative post-translational modifications (Ox-PTMs), including sulfenylation, disulfide bond formation, S-nitrosylation, and glutathionylation[1][6][7]. These modifications act as reversible molecular switches regulating protein function, enzyme activity, signaling pathways, and even gene expression[3][5][6]. While reversible cysteine oxidation is crucial for regulated signal transduction, cell cycle progression, apoptosis, immune responses, and metabolic adaptation, irreversible modification occurs under pathological oxidative stress and is implicated in diseases like cancer, cardiovascular disorders, neurodegeneration, inflammation, and diabetes[5][7]. Methods like mass spectrometric cysteine labelling enable proteome-wide profiling of these modifications, providing insight into cellular redox status and pathobiology[7]. Importantly, cysteine redox modulation is not a traditional drug target but represents a ubiquitous regulatory mechanism in molecular biology and disease[7][6][5]. In summary, "Protein Cysteine Residues & Reactive Oxygen Species" refers to a widespread regulatory process where oxidative modification of protein cysteines by ROS shapes cellular functions and disease, rather than a single molecule or canonical therapeutic target.

Other names

Cysteine redox modificationCys oxidationCysteine post-translational modificationCys Ox-PTM

Redox modulation (reversible oxidation/reduction); Inhibition/activation of enzyme activity via thiol oxidation; Disruption/restoration of signaling cascades; Indirectly through oxidative stress induction or amelioration