title: Enharncement of the hemolytic activity of the second component of human complement by oxidation.
abstract: A method has been described for the chemical modification of human C'2 which results in a pronounced enhancement of its hemolytic activity and a marked increase in the stability of the intermediate complex EAC'1a,4,2a prepared with the modified C'2. Both effects are fully explained by the observed increase in activity and stability of the C'3 converting enzyme, C'4,2a, following its generation with modified C'2. Evidence has been presented in support of the hypothesis that the modification resulting from treatment of C'2 with a critical concentration of iodine consists of oxidation of one or more sulfhydryl group within the molecule.
mesh_terms: D000818:Animals; D001681:Biological Assay; D003165:Complement System Proteins / Q000032:analysis / Q000502:physiology*; D003545:Cysteine / Q000494:pharmacology; D004492:Edetic Acid / Q000494:pharmacology; D004950:Esterases / Q000032:analysis; D005978:Glutathione / Q000494:pharmacology; D006461:Hemolysis / Q000187:drug effects*; D006801:Humans; D007120:Immunochemistry; D066298:In Vitro Techniques; D007455:Iodine / Q000494:pharmacology; D007461:Iodoacetates / Q000494:pharmacology; D008623:Mercaptoethanol / Q000494:pharmacology; D010084:Oxidation-Reduction; D011817:Rabbits; D012756:Sheep; D013438:Sulfhydryl Compounds / Q000494:pharmacology*
chemical_list: D007461:Iodoacetates; D013438:Sulfhydryl Compounds; D008623:Mercaptoethanol; D003165:Complement System Proteins; D007455:Iodine; D004492:Edetic Acid; D004950:Esterases; D005978:Glutathione; D003545:Cysteine