Evolutionary Relationships among Virulence-Associated Histidine Kinases

A strong relationship between virulence-associated sensor histidine kinases of fungi and those in Streptomyces coelicolor was observed, and phylogenetic analysis suggested that bacterium-to-eukaryote horizontal gene transfer had occurred between ancestors of these organisms. Phylogenetic analysis also identified a group of histidine kinases orthologous to the Streptomyces proteins that includes Pseudomonas aeruginosa GacS. We provide evidence that GacS is important for swarming motility, lipase production, and virulence in mice and had evolved to have partial functional overlaps with PhoQ, a less-related virulence-associated histidine kinase.