A bacteriophage contributes to the pathogenicity of the plague bacillus
Yersinia pestis, the plague bacillus, has an exceptional pathogenicity but the factors responsible for its extreme virulence are still unknown. A genome comparison with its less virulent ancestor Yersinia pseudotuberculosis identified a few Y. pestis-specific regions acquired after their divergence. One of them potentially encodes a prophage (YpfPhi), similar to filamentous phages associated with virulence in other pathogens. YpfPhi forms filamentous phage particles infectious for other Y. pestis isolates. Deletion of the YpfPhi genome does not affect Y. pestis ability to colonize and block the flea proventriculus, but results in an alteration of Y. pestis pathogenicity in mice. Transformation of Y. pestis from a classical enteropathogen to the highly virulent plague bacillus was accompanied by the acquisition of an unstable filamentous phage. Continued maintenance of YpfPhi despite its high in vitro instability suggests that it confers selective advantages to Y. pestis under natural conditions. This study represents the first characterization of a chromosomal element acquired by Y. pestis after its emergence from its recent ancestor Y. pseudotuberculosis and which may have participated in its evolution towards a deadly pandemic pathogen.
Related:
- Ancient Plague
- How plague bacterium Yersinia pestis damages eukaryotic cells
- Plague: From the 14th to the 21st century and still going strong
[...] A bacteriophage contributes to the pathogenicity of the plague bacillus [...]