Disulfide bond in mucus proteins (null)

Disulfide bonds in mucus proteins are covalent linkages between cysteine residues, primarily in large glycoproteins called mucins (e.g., MUC2, MUC5AC, MUC5B). These bonds facilitate the folding, stability, and multimerization of mucins, forming a dense, elastic matrix that constitutes the mucus gel barrier in the gastrointestinal and respiratory tracts[1][2][4][7]. The structure and function of mucus rely greatly on these crosslinks: intermolecular disulfide bonds organize mucin polymers into networks critical for trapping pathogens and protecting epithelial tissue[1][2][3][7]. Drugs classified as mucolytics, such as N-acetylcysteine, act by breaking these disulfide bonds, reducing gel viscosity and aiding clearance in diseases characterized by mucus hypersecretion or impaired mucociliary transport (e.g., asthma, cystic fibrosis)[6][7]. While reduction of disulfide bonds can alleviate symptoms of mucostasis, disruption of the polymeric network may compromise the protective role of mucus against infection and tissue damage[1][2][7]. Thus, disulfide bonds in mucus proteins represent a functional, though chemically defined, therapeutic target rather than a discrete biomolecule.

Other names

Disulfide bridges in mucinsS-S bonds in mucusintermolecular disulfide bonds in mucin glycoproteins

Reduction (cleavage) of disulfide bonds to decrease mucus viscosity and elasticity