The sheathed flagellum of Brucella melitensis is involved in persistence in a murine model of infection

@article{Fretin2005TheSF,
  title={The sheathed flagellum of Brucella melitensis is involved in persistence in a murine model of infection},
  author={David Fretin and Alan Fauconnier and Stephan K{\"o}hler and Shirley M. Halling and S L{\'e}onard and C Nijskens and Jonathan Ferooz and Pascal Lestrate and Rose-May Delrue and Isabelle Danese and Jessica Vandenhaute and Anne Tibor and Xavier Debolle and Jean-Jacques Letesson},
  journal={Cellular Microbiology},
  year={2005},
  volume={7}
}
Persistence infection is the keystone of the ruminant and human diseases called brucellosis and Malta fever, respectively, and is linked to the intracellular tropism of Brucella spp. While described as non‐motile, Brucella spp. have all the genes except the chemotactic system, necessary to assemble a functional flagellum. We undertook to determine whether these genes are expressed and are playing a role in some step of the disease process. We demonstrated that in the early log phase of a growth… 
The Three Flagellar Loci of Brucella ovis PA Are Dispensable for Virulence in Cellular Models and Mice
TLDR
A panel of B. ovis PA mutants defective in one, two or the three flagellar loci in order to assess their role in virulence of this rough (lacking O-polysaccharide) Brucella species is constructed and evidence new relevant differences between B. Ovis and B. melitensis are found.
The invA gene of Brucella melitensis is involved in intracellular invasion and is required to establish infection in a mouse model
TLDR
Results indicate that the invA gene is important during invasion but not for intracellular replication, and in vivo infection results demonstrated that spleen colonization was significantly lower with the mutant than with the parental strain.
Brucella and Its Hidden Flagellar System
TLDR
The study of these flagellar genes gives the genus Brucella a very high infectious versatility, placing it among the main organisms in urgent need of study, as it is linked to human health by direct contact with farm animals and by eventual transmission to the general population.
FtcR Is a New Master Regulator of the Flagellar System of Brucella melitensis 16M with Homologs in Rhizobiaceae
TLDR
The role of FtcR as a flagellar master regulator in B. melitensis and perhaps in other related alpha-proteobacteria is supported and VjbR, a quorum-sensing regulator of the LuxR family, is found to control fliF and flgE gene expression.
Brucella melitensis MucR, an Orthologue of Sinorhizobium meliloti MucR, Is Involved in Resistance to Oxidative, Detergent, and Saline Stresses and Cell Envelope Modifications
TLDR
The characterization of Brucella melitensis mucR, which encodes a zinc finger transcriptional regulator that has previously been shown to be involved in cellular and mouse infections at early time points, is reported, which reinforces the idea that there is a common conserved circuitry between plant symbionts and animal pathogens that regulates the relationship they have with their hosts.
Brucella: a pathogen without classic virulence genes.
Brucellosis Vaccines: Assessment of Brucella melitensis Lipopolysaccharide Rough Mutants Defective in Core and O-Polysaccharide Synthesis and Export
TLDR
It is demonstrated that no rough mutant is equal to Rev 1 in laboratory models and the notion that rough vaccines are suitable for the control of brucellosis in endemic areas is questioned.
Internal affairs: investigating the Brucella intracellular lifestyle.
TLDR
Understanding how Brucella molecules interplay with their host cell targets to modulate cellular functions and establish the intracellular niche will help unravel how this pathogen causes disease.
Genome Degradation in Brucella ovis Corresponds with Narrowing of Its Host Range and Tissue Tropism
TLDR
The results suggest that inactivation of genes involved in nutrient acquisition and utilization, cell envelope structure and urease may have played a role in narrowing of the tissue tropism and host range of B. ovis.
The stringent response mediator Rsh is required for Brucella melitensis and Brucella suis virulence, and for expression of the type IV secretion system virB
TLDR
It is concluded that in the intramacrophagic environment encountered by Brucella, Rsh might participate in the adaptation of the pathogen to low‐nutrient environments, and indirectly in the VirB‐mediated formation of the final replicative niche.
...
...

References

SHOWING 1-10 OF 89 REFERENCES
Flagellum of Legionella pneumophilaPositively Affects the Early Phase of Infection of Eukaryotic Host Cells
TLDR
It is demonstrated that the flagellum of L. pneumophila positively affects the establishment of infection by facilitating the encounter of the host cell as well as by enhancing the invasion capacity.
Identification of the Perosamine Synthetase Gene ofBrucella melitensis 16M and Involvement of Lipopolysaccharide O Side Chain in BrucellaSurvival in Mice and in Macrophages
TLDR
The results suggested that S-LPS or, more precisely, its O side chain is essential for survival in mice but not in macrophages.
Identification and characterization of in vivo attenuated mutants of Brucella melitensis
TLDR
The mutants selected in this study provide new insights into the molecular basis of Brucella virulence and are characterized for their ability to replicate in murine macrophages and in HeLa cells.
Requirement of flhA for Swarming Differentiation, Flagellin Export, and Secretion of Virulence-Associated Proteins in Bacillus thuringiensis
TLDR
The characterization of a mini-Tn10 mutant of B. thuringiensis that is defective in flagellum filament assembly and in swimming and swarming motility as well as in the production of hemolysin BL and phosphatidylcholine-preferring phospholipase C is described.
Identification of Brucella spp. genes involved in intracellular trafficking
TLDR
The preponderance of virB mutants demonstrates the importance of this secretion apparatus in the intracellular multiplication of B. melitensis and examines the intrACEllular fate of three VirB mutants in HeLa cells by immunofluorescence.
Identification of Brucella suis Genes Affecting Intracellular Survival in an In Vitro Human Macrophage Infection Model by Signature-Tagged Transposon Mutagenesis
TLDR
To identify new virulence factors, signature-tagged transposon mutagenesis is adapted to an in vitro human macrophage infection model and 14 different genes involved in intracellular survival or biosynthesis of smooth lipopolysaccharide were identified, thus validating the model.
Major Outer Membrane Protein Omp25 of Brucella suis Is Involved in Inhibition of Tumor Necrosis Factor Alpha Production during Infection of Human Macrophages
TLDR
Omp25 of B. suis is involved in the negative regulation of TNF-α production upon infection of human macrophages, which is associated with a nonidentified protein released into culture medium.
Type III Secretion Homologs Are Present in Brucella melitensis, B. ovis, and B. suis biovars 1, 2, and 3
TLDR
It is not yet known whether the genes are the cryptic remnants of a flagellar system or are actively involved in a process contributing to pathogenicity or previously undetected motility, but they are distributed widely in Brucella and merit further study to determine their role.
FlaC, a protein of Campylobacter jejuni TGH9011 (ATCC43431) secreted through the flagellar apparatus, binds epithelial cells and influences cell invasion
TLDR
The characterization of a protein designated FlaC, homologous to the N‐ and C‐terminus of the C. jejuni flagellin proteins, but lacks the central portion of these proteins, is reported, suggesting that FlaC plays an important role in cell invasion.
...
...