title: Influence of culture conditions on expression of antigens in Bordetella bronchiseptica.
abstract: Bordetella (B.) bronchiseptica isolates from the respiratory tract of rat and pig in their virulent phase-I and their spontaneously developed avirulent phase-III were investigated. The strains were cultured on Bordet-Gengou agar, on nutrition agar with 10% horse blood, and with 5% sheep blood, on yeast agar, on minimal nutrition agar (MM) and Simmon's citrate agar with glycerol, starch, and nicotinic acid. Antigenic modulation was induced by MgSO4 on Bordet-Gengou agar. The B. bronchiseptica strains were cultivated at 37 degrees C for 48 h. The influence of different MgSO4 concentrations after five passages (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 50, 100 mM/ml and low (20 degrees C) and high (42 degrees C) temperatures on antigenic modulation was investigated on Bordet-Gengou (B-G) agar. B. bronchiseptica colonies were characterized in relation to morphology, haemolysis, slide agglutination with B. bronchiseptica phase-I polyclonal antibodies, haemagglutination with horse and calf erythrocytes and polypeptide and LPS patterns in SDS-PAGE. Cultivation of B. bronchiseptica phase-I on B-G agar and ACMM agar at 37 degrees C for 48 h resulted in strong phase-I antigenic patterns, and, on peptone-rich media, in antigenic modulation. The morphology of B. bronchiseptica phase-I-strain colonies on peptone media was different from that of B-G and ACMM agar. The LPS pattern of both strains resembled that of phase-III strains. MgSO4 concentrations of 1 mM/ml (strain 1636 I) and 3 mM/ml (Ratte I) were able to induce LPS-pattern-like phase III.
authors.affiliation: Universität Leipzig, Vet. med. Fakultät, Direktorin des Instituts für Mikrobiologie, und Infektionskrankheiten, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Kasprzak
authors.forename: E
authors.initials: E
authors.lastname: Rehak
authors.forename: M
authors.initials: M
authors.lastname: Krüger
mesh_terms: D000372:Agglutination Tests / Q000662:veterinary; D000818:Animals; D000942:Antigens, Bacterial / Q000096:biosynthesis*; D016950:Bordetella bronchiseptica / Q000187:drug effects / Q000276:immunology*; D003470:Culture Media; D004591:Electrophoresis, Polyacrylamide Gel; D008278:Magnesium Sulfate / Q000494:pharmacology; D051381:Rats; D013552:Swine; D013696:Temperature
chemical_list: D000942:Antigens, Bacterial; D003470:Culture Media; D008278:Magnesium Sulfate