title: Conservation of antigenicity in a 31-kDa Brucella protein.
abstract: A 31-kilodalton (kDa) protein extracted from Brucella abortus was previously cloned into Escherichia coli and expressed at high levels. The E. coli-derived protein can be purified by a simple 2-step procedure entailing detergent extraction followed by ion-exchange chromatography. Subsequent analyses show that the E. coli-derived protein is identical to the Brucella-derived protein in molecular weight and isoelectric point. A partial amino acid sequence of the N-terminus of the protein of E. coli origin matches the predicted sequence, based on DNA sequence data. Using specific antiserum raised against the E. coli-derived protein, 34 strains of Brucella, representing all 6 recognized species, were examined for expression of the 31-kDa protein by Western blotting. This protein was detectable in all, but one Brucella species (B. ovis), including all 8 biovars of B. abortus tested. This degree of conservation supports further study of the 31-kDa protein for potential exploitation as a vaccine or diagnostic component.
authors.affiliation: National Animal Disease Center, ARS, USDA, Ames, IA 50010.
authors.forename: B J
authors.initials: BJ
authors.lastname: Bricker
authors.forename: L B
authors.initials: LB
authors.lastname: Tabatabai
authors.forename: B L
authors.initials: BL
authors.lastname: Deyoe
authors.forename: J E
authors.initials: JE
authors.lastname: Mayfield
mesh_terms: D000595:Amino Acid Sequence; D000942:Antigens, Bacterial / Q000276:immunology*; D001426:Bacterial Proteins / Q000276:immunology* / Q000302:isolation & purification; D015153:Blotting, Western; D002003:Brucella abortus / Q000276:immunology*; D002852:Chromatography, Ion Exchange; D004591:Electrophoresis, Polyacrylamide Gel; D007525:Isoelectric Focusing; D008969:Molecular Sequence Data; D008970:Molecular Weight
chemical_list: D000942:Antigens, Bacterial; D001426:Bacterial Proteins