title: Influence of modifications of physicochemical and biological properties of haptoglobin. VII. Immunochemical reactivity of haptoglobin with modified tyrosine residues.
abstract: Tyrosine residues in human haptoglobin (Hp) type 2-1 were modified by treatment with various amounts of N-acetylimidazole, iodine or tetranitromethane. Rabbit antisera directed against native Hp, Ac-Hp, 1-Hp and NO2-Hp in cross-reactions by immunoprecipitation showed serologic identify of native Hp and most of the modified derivatives, with the exception of derivatives modified by means of a high excess of N-acetylimidazole, which showed partial identity with remaining preparations, irrespective of the antiserum used. The results indicate that tyrosine residues play no essential role in the immunochemical reactivity of haptoglobin.
mesh_terms: D000107:Acetylation; D000818:Animals; D000937:Antigen-Antibody Reactions; D003429:Cross Reactions; D006242:Haptoglobins / Q000276:immunology / Q000494:pharmacology*; D007093:Imidazoles / Q000494:pharmacology; D005779:Immunodiffusion; D007455:Iodine / Q000494:pharmacology; D011817:Rabbits; D013774:Tetranitromethane / Q000494:pharmacology; D014443:Tyrosine
chemical_list: D006242:Haptoglobins; D007093:Imidazoles; D014443:Tyrosine; D007455:Iodine; D013774:Tetranitromethane