CemR atypical response regulator impacts energy conversion inCampylobacteria

Abstract

AbstractCampylobacter jejuniandArcobacter butzleriare microaerobic food-borne human gastrointestinal pathogens that mainly cause diarrheal disease. These related species of theCampylobacteriaclass face variable atmospheric environments during infection and transmission, ranging from nearly anaerobic to aerobic conditions. Consequently, their lifestyles require that both pathogens need to adjust their metabolism and respiration to the changing oxygen concentrations of the colonization sites. Our studies revealed thatC. jejuniandA. butzlerilacking aCampylobacteria-specific regulatory protein,C. jejuniCj1608 or a homologueA. butzleriAbu0127, are unable to reprogram tricarboxylic acid cycle or respiration pathways, respectively, to produce ATP efficiently and, in consequence, adjust growth to changing oxygen supply. We propose that theseCampylobacterialenergy and metabolism regulators (CemR) are long-sought transcription factors controlling the metabolic shift related to oxygen availability, essential for these bacteria’s survival and adaptation to the niches they inhabit.