Temporal and differential regulation of expression of the eukaryotic-like ankyrin effectors of Legionella pneumophila
Article first published online: 30 MAR 2010
© 2010 Society for Applied Microbiology and Blackwell Publishing Ltd
Environmental Microbiology Reports
Volume 2, Issue 5, pages 677–684, October 2010
How to Cite
Al-Khodor, S., Al-Quadan, T. and Abu Kwaik, Y. (2010), Temporal and differential regulation of expression of the eukaryotic-like ankyrin effectors of Legionella pneumophila. Environmental Microbiology Reports, 2: 677–684. doi: 10.1111/j.1758-2229.2010.00159.x
- Issue published online: 30 MAR 2010
- Article first published online: 30 MAR 2010
- Received 16 December, 2009; accepted 8 February, 2010.
Upon transition from the exponential (E) to the post-exponential phase (PE) of growth, Legionella pneumophila undergoes a phenotypic modulation from a replicative to a highly infectious form. This transition requires a delicate regulatory cascade that is triggered to induce expression of various virulence-related genes. We have recently characterized eleven L. pneumophila eukaryotic-like ankyrin effectors (Ank) shared between the four sequenced genomes of L. pneumophila. The AnkB effector recruits polyubiquitinated proteins to the Legionella-containing vacuole (LCV). It is not known whether expression of the ank genes is regulated by various regulators triggered at the PE phase and whether this regulation is essential for function. Here we show that temporal and differential regulation of the ank genes is mediated by RelA, the enhancer protein LetE, and the two component systems LetA/S and PmrA/B. Consistent with the expression of ankB at the PE phase, we show that bacteria grown to the PE but not the E phase recruit polyubiquitinated proteins to the LCV within Acanthamoeba in an AnkB-dependant mechanism. We conclude that the genes encoding the eukaryotic-like Ank effectors of L. pneumophila are temporally and spatially regulated at the PE phase.