Speaker
Description
Classical Brucella are host-adapted, zoonotic pathogens that replicate within macrophages of their hosts. Recently, atypical Brucella strains have been isolated from rodents, amphibians and soil. These Brucella isolates are genetically more similar to environmental Ochrobactrum spp., raising questions about their niches and zoonotic potential. This study explores whether free-living amoebae, which share phagocytic traits with macrophages, serve as reservoirs for these atypical Brucella.
We tested B. microti, three amphibian-derived Brucella isolates and two Ochrobactrum isolates for growth under different abiotic factors, as well as their interactions with amoeba (Dictyostelium discoideum and Acanthamoeba castellanii). All tested bacteria tolerated acidic culture conditions. The temperature optimum for B. microti and Ochrobactrum was at 28°C, but it varied for the other isolates. Preliminary data from macrophage infection assays confirmed intracellular replication of B. microti and amphibian-derived isolates. The latter resisted phagocytosis on an amoeba monolayer. In buffer, two of the amphibian-derived isolates showed increased proliferation in co-cultures with D. discoideum.
These findings suggest that atypical Brucella benefit from amoebae and thus might support their persistence in the environment. The ability of atypical Brucella to withstand acidic conditions, to adapt to lower temperatures, and to replicate in macrophages supports the hypothesis of a dual lifestyle in environmental and host-associated niches.
Keywords
Brucella, Ochrobactrum, Amoebae, Infection, Host cell interaction
| Registration ID | OHS25-136 |
|---|---|
| Professional Status of the Speaker | PhD Student |
| Junior Scientist Status | Yes, I am a Junior Scientist. |
Author
Co-authors
External references
- 53
