Disulfide bond in proteins

Disulfide bonds in proteins are covalent linkages formed between the sulfur atoms of two cysteine residues and serve as essential post-translational structural elements, predominantly in secreted and extracellular proteins and peptides[1][2][3][5][6]. They stabilize protein tertiary and quaternary structure, facilitate correct protein folding during synthesis (especially in the endoplasmic reticulum), and can act as redox-sensitive switches modulating protein activity in processes ranging from enzyme catalysis to allosteric regulation[1][4][6]. Impairments in correct disulfide bond formation or isomerization are implicated in several protein misfolding diseases and oxidative stress-related conditions, but the bonds themselves are not direct drug targets in the conventional sense[1][3][6]. Selective modulation of thiol–disulfide exchange (e.g., by inhibiting protein disulfide isomerase) is under investigation for disease-modifying therapy, but systemic targeting of disulfide bonds carries significant risk due to their critical role in normal protein homeostasis[5][6]. Note: - "Disulfide bonds in proteins/peptides" is not a canonical therapeutic target (such as a receptor, enzyme, or transporter), but rather a chemical modification or structural element. For structured databases, it should be classified as a post-translational modification or excluded as a conventional molecular drug target[1][2][5]. - This entry aggregates consensus information but does not correspond to a single protein, gene, or druggable entity.

Other names

Disulfide bridgeS–S bondProtein disulfidePeptide disulfide

Alteration of thiol-disulfide exchange to modify protein structure/activity[6]; Reduction or formation of disulfide bonds to alter protein folding/stability[1][5]; Allosteric regulation through selective cleavage of disulfide in target proteins[6]