Genomic sequence analysis revealed that all bacteria of the genus
Bartonella are characterized by the presence of a
Bartonella-specific GTA (BaGTA), which shares no homologies to previously described GTA systems. BaGTA is encoded upstream from an origin of run-off replication (ROR), another conserved feature of
Bartonella genomes that has been suggested to be linked to BaGTA activity. Phylogenetic analyses identified BaGTA as a key innovation associated with the adaptive radiation that characterizes these
zoonotic bacterial pathogens. Although BaGTA is not directly linked to Bartonella pathogenicity, it has been proposed to drive the exchange and the diversification of host-interaction factors within Bartonella communities such as VirB type IV secretion system (
T4SS) and its cognate Bartonella effector proteins. Maintenance of BaGTA is likely driven by selection to increase the likelihood of genetic exchange and facilitates adaptation to host-specific defense systems during infection. ==Role==