title: Analysis of the immunoactivator sites of parotid protein isolated from bovine parotid glands.
abstract: Parotid protein (parotin) was isolated from bovine parotid glands. To analyze the active site of parotid protein, the parotid subunit (PS) was digested by trypsin and then fractionated on a Sephadex G-25 column. Fraction A induced mainly polyclonal antibody responses and interleukin 1 (IL-1)-like activities. FrAA-1, consisting of 58 amino acids (LYILYFFQSDNEDKEKVVRQEEGEE-RITALLMNGSALKQEEWWEKEDTDDTAIVLLK) was isolated from fraction A by chromatography on QAE-Sephadex A-25 columns. FrAA-1 was found to possess IL-1-like activity. There was only 29% homology between FrAA-1 and four IL-1 molecules. When 10- and 20-residue peptides based on the amino acid sequence of FrAA-1 were synthesized, P-10.2 (TDDTAIVLLK) alone exerted an IL-1-like effect on C3H/HeJ thymocytes, whereas P-20.1 (SDNEDKEKVVRQEEGEERIT) alone elicted polyclonal IgM and IgG antibody production in human lymphocytes. These results suggest that the active sites for polyclonal B-cell activator (PBA) and IL-1-like activity have different locations in FrAA-1.
authors.affiliation: Third Department of Internal Medicine, Nara Medical University, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Ishizaka
authors.forename: T
authors.initials: T
authors.lastname: Tsujii
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000917:Antibody Formation; D001665:Binding Sites; D002417:Cattle / Q000235:genetics / Q000276:immunology; D002478:Cells, Cultured; D006801:Humans; D007375:Interleukin-1 / Q000096:biosynthesis / Q000235:genetics; D008214:Lymphocytes / Q000187:drug effects / Q000276:immunology; D051379:Mice; D008809:Mice, Inbred C3H; D008811:Mice, Inbred DBA; D008969:Molecular Sequence Data; D010306:Parotid Gland / Q000737:chemistry / Q000276:immunology; D010446:Peptide Fragments / Q000138:chemical synthesis / Q000276:immunology / Q000494:pharmacology; D012471:Salivary Proteins and Peptides / Q000235:genetics / Q000276:immunology* / Q000494:pharmacology; D012689:Sequence Homology, Nucleic Acid
chemical_list: D007375:Interleukin-1; D010446:Peptide Fragments; D012471:Salivary Proteins and Peptides