title: Structural analysis and demonstration of the 29 kDa antigen of pathogenic Entamoeba histolytica as the major accessible free thiol-containing surface protein.
abstract: The 29 kDa protein of pathogenic Entamoeba histolytica is a cysteine-rich surface antigen which we recently characterized by cDNA sequencing and by using monoclonal antibodies which differentiated between pathogenic and non-pathogenic clinical isolates. To determine the structure and biochemical attributes of this protein, a repertoire of immunological techniques using monoclonal antibodies, and radiolabelling were employed. We demonstrated that the 29 kDa protein forms a 60 kDa dimer and a high-molecular-mass oligomer(s) on the surface of the organism through disulphide bonds, and is the major accessible free thiol-containing surface protein of E. histolytica. The deduced amino acid sequence encoding the 29 kDa protein was found to share a common amino acid domain with sequences reported for Helicobacter pylori, Salmonella typhimurium, MER5 gene expressed in murine erythroleukemia cells, Clostridium pasteurianum, and a Bacillus spp.
authors.affiliation: Department of Pharmaceutical Sciences, College of Pharmacy, Idaho State University, Pocatello 83209-8334.
authors.forename: B M
authors.initials: BM
authors.lastname: Flores
authors.forename: M A
authors.initials: MA
authors.lastname: Batzer
authors.forename: M A
authors.initials: MA
authors.lastname: Stein
authors.forename: C
authors.initials: C
authors.lastname: Petersen
authors.forename: D L
authors.initials: DL
authors.lastname: Diedrich
authors.forename: B E
authors.initials: BE
authors.lastname: Torian
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D000913:Antibodies, Protozoan / Q000276:immunology; D000953:Antigens, Protozoan / Q000737:chemistry* / Q000276:immunology; D002850:Chromatography, Gel; D016384:Consensus Sequence; D004591:Electrophoresis, Polyacrylamide Gel; D004748:Entamoeba histolytica / Q000276:immunology*; D000939:Epitopes / Q000276:immunology; D015151:Immunoblotting; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010084:Oxidation-Reduction; D010449:Peptide Mapping; D011487:Protein Conformation; D017386:Sequence Homology, Amino Acid; D013438:Sulfhydryl Compounds / Q000737:chemistry*
chemical_list: D000911:Antibodies, Monoclonal; D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D000939:Epitopes; D013438:Sulfhydryl Compounds