The BvgS PAS Domain, an Independent Sensory Perception Module in the Bordetella bronchiseptica BvgAS Phosphorelay

Despite high rates of vaccination, pertussis, a severe, highly contagious respiratory disease caused by the bacteriumBordetella pertussis , has reemerged as a significant health threat. InBordetella pertussis and the closely related speciesBordetella bronchiseptica , activity of the BvgAS two-component regulatory system is critical for colonization of the mammalian respiratory tract. We show here that the cytoplasmic PAS domain of BvgS can function as an independent signal perception domain that influences BvgS activity in response to environmental conditions. Our work is significant because it reveals a critical, yet previously unrecognized, role for the PAS domain in the BvgAS phosphorelay and provides a greater understanding of virulence regulation inBordetella .