Salmonella enterica serovar Dublin strains which are Vi antigen-positive use type IVB pili for bacterial self-association and human intestinal cell entry.

Some strains of Salmonella enterica serovar Dublin are Vi antigen-positive. S. enterica serovar Typhi uses Type IVB pili, encoded adjacent to the viaB locus required for Vi antigen synthesis, to facilitate both eukaryotic cell attachment and bacterial self-association under conditions that favour DNA supercoiling.

Analysis of Salmonella enterica serotype-host specificity in calves: avirulence of S. enterica serotype gallinarum correlates with bacterial dissemination from mesenteric lymph nodes and persistence in vivo.

Host and bacterial factors that determine whether Salmonella serotypes remain restricted to the gastrointestinal tract or penetrate beyond the mucosa and cause systemic disease remain largely undefined. Here, factors influencing Salmonella host specificity in calves were assessed by characterizing the pathogenesis of different serotypes. Salmonella enterica serotype Dublin was highly virulent intravenously, whereas S.

An Inv/Mxi-Spa-like type III protein secretion system in Burkholderia pseudomallei modulates intracellular behaviour of the pathogen.

Burkholderia pseudomallei is the causative agent of melioidosis, a serious infectious disease of humans and animals that is endemic in subtropical areas. B. pseudomallei is a facultative intracellular pathogen that may invade and survive within eukaryotic cells for prolonged periods.

Interaction of Salmonella serotypes with porcine macrophages in vitro does not correlate with virulence.

The interaction between Salmonella serotypes and macrophages is potentially instrumental in determining the outcome of infection. The nature of this interaction was characterized with respect to virulence and serotype-host specificity using pigs as the infection model. Experimental infection with Salmonella typhimurium, Salmonella choleraesuis or Salmonella dublin resulted in enteric, systemic or asymptomatic infection, respectively, which correlates well with the association of S.