The perplexing functions and surprising origins of Legionella pneumophila type IV secretion effectors.
Cell Microbiol
; 11(10): 1435-43, 2009 Oct.
Article
em En
| MEDLINE
| ID: mdl-19563462
ABSTRACT
Only a limited number of bacterial pathogens evade destruction by phagocytic cells such as macrophages. Legionella pneumophila is a Gram-negative gamma-proteobacterial species that can infect and replicate in alveolar macrophages, causing Legionnaires' disease, a severe pneumonia. L. pneumophila uses a complex secretion system to inject host cells with effector proteins capable of disrupting or altering the host cell processes. The L. pneumophila effectors target multiple processes but are essentially aimed at modifying the properties of the L. pneumophila phagosome by altering vesicular trafficking, gradually creating a specialized vacuole in which the bacteria replicate robustly. In nature, L. pneumophila is thought to parasitize free-living protists, which may have selected for traits that promote virulence of L. pneumophila in humans. Indeed, many effector genes encode proteins with eukaryotic domains and are likely to be of protozoan origin. Sustained horizontal gene transfer events within the protozoan niche may have allowed L. pneumophila to become a professional parasite of phagocytes, simultaneously giving rise to its ability to infect macrophages, cells that constitute the first line of cellular defence against bacterial infections.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas de Bactérias
/
Legionella pneumophila
/
Evolução Molecular
/
Fatores de Virulência
Tipo de estudo:
Prognostic_studies
Limite:
Animals
/
Humans
Idioma:
En
Revista:
Cell Microbiol
Ano de publicação:
2009
Tipo de documento:
Article