An aromatic amino acid auxotrophic mutant of Bordetella bronchiseptica is attenuated and immunogenic in a mouse model of infection.

We have constructed an aromatic amino acid auxotrophic mutant of Bordetella bronchiseptica, harbouring mutations in aroA and trpE to investigate the use of such a strain as a live-attenuated vaccine. B. bronchiseptica aroA trpE was unable to grow in minimal medium without aromatic supplementation.

Role played by the response regulator Ris in Bordetella bronchiseptica resistance to macrophage killing.

Previous studies suggested that the persistence in eukaryotic cells of a Bordetella bronchiseptica mutant carrying an insertion in the locus encoding the response regulator RisAS is impaired. This suggested that ris-dependent products are required for the intracellular survival of bacteria. In this study we demonstrate that ris-regulated products play a role in B.

Role of phosphoglucomutase of Bordetella bronchiseptica in lipopolysaccharide biosynthesis and virulence.

The phosphoglucomutase (PGM)-encoding gene of Bordetella bronchiseptica is required for lipopolysaccharide (LPS) biosynthesis. An insertion mutant of the wild-type B. bronchiseptica strain BB7865 which disrupted LPS biosynthesis was created and characterized (BB7865pgm).

Interaction of Salmonella enterica serotype Typhimurium with dendritic cells is defined by targeting to compartments lacking lysosomal membrane glycoproteins.

Dendritic cells (DCs) play a central role in the generation of acquired immunity to infections by pathogenic microorganisms. Salmonella enterica serotype Typhimurium is known to survive and proliferate intracellularly within macrophages and nonphagocytic cells, but no data exist on how this pathogen interacts with DCs. In this report, we show the capacity of serotype Typhimurium to survive within the established mouse DC line CB1.

A second two-component regulatory system of Bordetella bronchiseptica required for bacterial resistance to oxidative stress, production of acid phosphatase, and in vivo persistence.

Random minitransposon mutagenesis was used to identify genes involved in the survival of Bordetella bronchiseptica within eukaryotic cells. One of the mutants which exhibited a reduced ability to survive intracellularly harbored a minitransposon insertion in a locus (ris) which displays a high degree of homology to two-component regulatory systems. This system exhibited less than 25% amino acid sequence homology to the only other two-component regulatory system described in Bordetella spp.