Identification of Icm protein complexes that play distinct roles in the biogenesis of an organelle permissive for Legionella pneumophila intracellular growth
Open Access
- 1 November 2000
- journal article
- research article
- Published by Wiley in Molecular Microbiology
- Vol. 38 (4), 719-736
- https://doi.org/10.1046/j.1365-2958.2000.02176.x
Abstract
Legionella pneumophila is a bacterial pathogen that can enter the human lung and grow inside alveolar macrophages. To grow within phagocytic host cells, the bacteria must create a specialized organelle that restricts fusion with lysosomes. Biogenesis of this replicative organelle is controlled by 24 dot and icm genes, which encode a type IV‐related transport apparatus. To understand how this transporter functions, isogenic L. pneumophila dot and icm mutants were characterized, and three distinct phenotypic categories were identified. Our data show that, in addition to genes that encode the core Dot/Icm transport apparatus, subsets of genes are required for pore formation and modulation of phagosome trafficking. To understand activities required for virulence at a molecular level, we investigated protein–protein interactions. Specific interactions between different Icm proteins were detected by yeast two‐hybrid and gel overlay analysis. These data support a model in which the IcmQ–IcmR complex regulates the formation of a translocation channel that delivers proteins into host cells, and the IcmS–IcmW complex is required for export of virulence determinants that modulate phagosome trafficking.Keywords
This publication has 57 references indexed in Scilit:
- The Legionella pneumophila IcmS–LvgA protein complex is important for Dot/Icm‐dependent intracellular growthMolecular Microbiology, 2006
- The Legionella pneumophila PilT Homologue DotB Exhibits ATPase Activity That Is Critical for Intracellular GrowthJournal of Bacteriology, 2004
- How is the intracellular fate of the Legionella pneumophila phagosome determined?Trends in Microbiology, 1998
- Conjugative Transfer by the Virulence System of Legionella pneumophilaScience, 1998
- Altered intracellular targeting properties associated with mutations in the Legionella pneumophila dotA geneMolecular Microbiology, 1994
- A novel genetic system to detect protein–protein interactionsNature, 1989
- Evidence for a gamma-interferon receptor that regulates macrophage tumoricidal activity.The Journal of Experimental Medicine, 1984
- Legionnaires' Disease Bacterium (Legionella pneumophila) Multiplies Intracellularly in Human MonocytesJCI Insight, 1980
- Legionnaires' DiseaseNew England Journal of Medicine, 1977
- Legionnaires' DiseaseNew England Journal of Medicine, 1977