IIBBA   05544
INSTITUTO DE INVESTIGACIONES BIOQUIMICAS DE BUENOS AIRES
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Brucella abortus oxygen sensing: the PrrB/PrrA and NtrY/NtrX two component systems
Autor/es:
CARRICA MARIELA; PARIS GASTON; GOLDBAUM FERNANDO
Lugar:
Puerto Madryn, Chubut
Reunión:
Congreso; XLVI Reunión Anual Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2010
Resumen:
Bacterias of the Brucella genera are facultative intracellular pathogens that produces abortion and infertility in animals and a febrile illness in humans. The pathogenicity of these bacterias is in part due to its ability to adapt to harsh conditions like microaerobic environments. The aim of this study is to elucidate the mechanisms by which Brucella can sense and adapt to low oxygen tension. We report the characterization of two B. abortus two-component system mutant strains: prrB::Km and ntrY::Km. The PrrB/PrrA system has been characterized as a redox-sensing system in other bacterias and is conserved in Brucella. The NtrY/NtrX system sense an unknown signal and regulates nitrogen fixation and metabolism in A. caulinodams. Brucella prrB::Km and ntrY::Km strains grow slowly than wild type strain in in vitro culture conditions. Infection of macrophages and mice is affected in the NtrY mutant but not in the PrrB mutant. Moreover, the NtrY expression is increased in anaerobic growth conditions and its expression is diminished in absence of PrrB, showing a correlation between both systems. In agreement, the in vitro growth of a double mutant ntrY/prrB genes is severally affected, in particular in microaerobic conditions. These results suggest that in Brucella NtrY/NtrX and PrrB/PrrA two-component systems are coordinately acting to adapt to  different enviromental conditions.