title: Intra- and intermolecular cross-linking of membrane proteins in intact erythrocytes and ghosts by SH-oxidizing agents.
abstract: In intact human erythrocytes, SH-oxidizing agents exclusively cross-link spectrin via disulfide bonds. In ghosts, additional dimerization of the major intrinsic protein, band 3, is observed. After blockade of intracellular GSH the agents dimerize band 3 in the intact cell too, indicating that GSH may prevent band 3 dimerization under physiological conditions. The oxidizing agents reversibly oxidize 80% of the membrane SH-groups, suggesting that these groups are arranged close enough to each other to form disulfide bonds. This arrangement may protect other cell cell structures against free radicals or oxidative stress.
mesh_terms: D001391:Azo Compounds / Q000494:pharmacology*; D002463:Cell Membrane Permeability; D003958:Diamide / Q000494:pharmacology*; D004910:Erythrocyte Membrane / Q000187:drug effects* / Q000378:metabolism; D004912:Erythrocytes / Q000187:drug effects*; D006801:Humans; D007461:Iodoacetates / Q000494:pharmacology; D008565:Membrane Proteins / Q000378:metabolism*; D010618:Phenanthrolines / Q000494:pharmacology*; D011487:Protein Conformation; D013049:Spectrin / Q000378:metabolism; D013776:Tetrathionic Acid / Q000494:pharmacology*; D013885:Thiosulfates / Q000494:pharmacology*
chemical_list: D001391:Azo Compounds; D007461:Iodoacetates; D008565:Membrane Proteins; D010618:Phenanthrolines; D013885:Thiosulfates; D003958:Diamide; D013049:Spectrin; D013776:Tetrathionic Acid