Survival of Legionella pneumophila in water. L. pneumophila is able to survive up to a year in water without the presence of any food source of susceptible protozoan. We are using microarray techniques to uncover the mechanism underlying long-term survival in water. We are also interested by the effect of environmental conditions on the transmission potential of L. pneumophila to human.
Legionella pneumophila cells in water stained with the Live/Dead kit.
Characterization of the small RNA expressed by L. pneumophila. Recent studies have identified 79 sRNAs expressed by L. pneumophila. Two of those sRNAs, called RsmY and RsmZ, functionally link three major response regulators of L. pneumophila virulence factors, the sigma factor RpoS, the RNA-binding proteins CsrA and the two-component system LetA/S. Another identified sRNA is a homolog of the 6S RNA of E. coli, which affects the balance between different RNAP holoenzymes. It is an important regulator of L. pneumophila virulence since a 6S RNA deletion mutant is unable to compete against the wild-type during intracellular growth. There is currently no insight into the role of the other identified sRNAs. Therefore, the goal of this project is to identified phenotypes controlled by the sRNAs expressed by L. pneumophila and to identify the target of the sRNAs associated with a phenotype.