Modulation of bacterial lifestyles via two-component regulatory networks

The ability of bacteria to survive in specific habitats requires the coordination of the expression of thousands of environmentally regulated genes. The complexity of these regulatory networks increases with the breadth of environments a bacterial species occupies. Species that are able to survive in a broad range of environments generally possess a large coding capacity and devote a significant portion of their genome to signal transduction and gene regulation. Myxococcus xanthus, a free-living bacterium known for its complex multicellular development and differentiation, uses 8% of its genome for regulation. In contrast, the habitat-restricted human pathogen Helicobacter pylori dedicates less than 2% of its genome toward this aim.