The Hfq Homolog in Legionella Pneumophila Demonstrates Regulation by LetA and RpoS and Interacts with the Global Regulator CsrA.

A gene in Legionella pneumophila that has significant homology to published hfq genes demonstrated regulation by RpoS and the transcriptional regulator LetA. Additionally, Hfq has a positive effect on the presence of transcripts of the genes for CsrA and the ferric uptake regulator Fur. Mutants lacking hfq demonstrate defects in growth and pigmentation and slight defects in virulence in both amoeba and macrophage infection models. Hfq appears to play a major role in exponential-phase regulatory cascades of L. pneumophila.