Deciphering bartonella diversity, recombination, and host specificity in a rodent community

Area of Science:

• Microbiology and Evolutionary Biology
• Host-Pathogen Interactions
• Genetics and Genomics

Background:

• Host specificity is a key trait in bacterial pathogens, shaped by co-evolutionary processes.
• Alpha-proteobacteria of the genus Bartonella are known erythrocyte parasites infecting diverse mammals, including rodents.
• Understanding Bartonella diversity and host association is crucial for comprehending pathogen evolution and transmission dynamics.

Purpose of the Study:

• To genetically analyze Bartonella diversity in a French suburban forest rodent community.
• To evaluate Bartonella's host specificity, recombination capacity, and genetic diversity in bank voles and wood mice.
• To investigate potential gene flow between Bartonella genotypes infecting different rodent hosts.

Main Methods:

• Genetic analysis of Bartonella from 550 collected rodents (bank voles and wood mice).
• Identification and genotyping of Bartonella species, including B. taylorii, B. grahamii, B. doshiae, and a novel B. rochalimae-like species.
• Comparative analysis of strain diversity and host association patterns.

Main Results:

• 63 distinct Bartonella genotypes were identified, with B. taylorii showing higher strain diversity than B. grahamii.
• Most Bartonella genotypes exhibited strong host specificity to either bank voles or wood mice.
• Three B. taylorii genotypes demonstrated a broader host range, and evidence of lateral gene transfer was observed between Bartonella from different hosts.

Conclusions:

• Bartonella populations in this rodent community exhibit significant genetic diversity and host specialization.
• The findings suggest potential bottlenecks in certain Bartonella species (e.g., B. grahamii).
• Lateral gene transfer occurs between Bartonella genotypes infecting different rodent hosts, indicating potential co-habitation and gene flow.