is an environmental bacterium that parasitizes aquatic protozoa and uses the same processes to infect humans. The facultative intracellular pathogen causes a life-threatening pneumonia with possible systemic complications. The co-evolution with protozoa is reflected in an armoury of bacterial effectors, and many of these type IV-secreted proteins have likely been acquired by interdomain horizontal gene transfer (HGT) from hosts. The unique features of are the largest bacterial effector repertoire known to date, subversion of virtually all eukaryotic signalling pathways and acquisition of eukaryotic enzyme activities used to manipulate the host cell to the pathogen’s advantage.

This study was supported by the:
  • Fondation pour la Recherche Médicale (Award EQU201903007847)
    • Principle Award Recipient: CarmenBuchrieser
  • Fondation pour la Recherche Médicale
    • Principle Award Recipient: HubertHilbi
  • Swiss National Science Foundation (Award 31003A_175557 and 310030_200706)
    • Principle Award Recipient: HilbiHubert
  • Agence Nationale de la Recherche (Award ANR-10-LABX-62-IBEID)
    • Principle Award Recipient: CarmenBuchrieser

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