Reactive oxygen species and exposed protein sulfur atoms (ROS (for Reactive oxygen species); no standard abbreviation for "exposed protein sulfur atoms")

Reactive oxygen species (ROS) are a chemically diverse class of highly reactive molecules derived from molecular oxygen, including superoxide (O₂•⁻), hydrogen peroxide (H₂O₂), and hydroxyl radicals (•OH)[5]. They play fundamental roles in cellular signaling, immune defense, and metabolism, but excess ROS causes oxidative damage to proteins, nucleic acids, and lipids, contributing to aging and chronic disease[5][4][7]. Exposed protein sulfur atoms, primarily found in cysteine and methionine residues, are prime molecular targets for ROS. Oxidation of these sulfur-containing amino acids triggers important redox-regulated post-translational modifications (such as disulfide formation, S-glutathionylation, or sulfoxide formation), which can change protein activity, localization, or interactions—thereby modulating processes such as apoptosis, immune response, and cell proliferation[1][3][6]. Because the term "Reactive Oxygen Species / Exposed Protein Sulfur Atoms" refers to a chemical reactivity relationship rather than a molecular entity, it is not a single therapeutic target but a motif or class of redox-biochemistry interactions; thus, while relevant to disease and drug action, it does not map to a single gene, protein, or canonical therapeutic target[1][3][5][6].

Other names

Reactive oxygen species (ROS)Protein cysteine thiolsProtein methionine residuesSulfur-containing amino acid side chainsOxidizable protein thiols

Scavenging ROS to prevent protein and DNA damage - Modifying cysteine/methionine residues to alter protein function - Redox-dependent post-translational modification of target proteins (e.g., S-sulfenylation, S-nitrosylation, S-persulfidation) - Reversing oxidized sulfur atom modifications (e.g., via methionine sulfoxide reductase)