Gizemli bakteri lejyonella: Büyük silah cephanesine sahip bir ordu mu?

The bacterium of the genus Legionella were first detected during the American Legion convention held in Philadelphia in 1976, following a largeoutbreak of severe pneumonia (among residents of the Bellevue-Stratford Hotel) isolated by Dr. Joseph McDade. Legionella is an environmental Gram-negative bacterium that can cause spontaneously healing febrile illnesses (Pontiacfever) and fatal pneumonia (Legionnaires' disease) in humans. Legionella pneumophila is an important cause of community- and hospital-acquired pneumonia. It is phagocytosed within alveolar macrophages or epithelial cells by inhalation of aerosols contaminated with Legionella. Legionnaires' disease is caused by the bacilli engulfed in alveolar macrophages forming a vacuole containing Legionella by preventing phagolysosomal fusion, thanks to the Type 4 Secretion System encoded by the Dot/Icm genes, and its proliferation within this vacuole by escaping the host immune mechanisms. The most interesting aspect of the Legionella bacterium's genome is the motifs, most of which are of eukaryotic origin, that it acquired through gene transfer during its parasitism in amoebae. Thanks to the semotifs obtained by horizontal gene transfer, Legionella bacteria have an incredible number of virulence factors that will increase their resistance to environmental factors and host immunity, that is, "an army with a huge arsenal". Moreover, these eukaryotic motifs also apply to bacteria; Provides the capacity to develop exceptional adaptation strategies. Their survival in biofilms and amoebae protects them from intensive disinfection practices and increases their resistance to environmental factors. The twophase life cycle of Legionella includes the infectious phase and the non-infective replicative phase; It also reveals physiological, morphogenetic and metabolic change abilities. Amoebae and macrophages suggests that environmental amoebae act as an "educator" the similarity of the infection cycle between. It is aimed to review current information on the abilities of Legionella to infect amoebae and macrophages, virulence/survival strategies, infection mechanisms, host immunity and Legionella immunopathogenesis. [ABSTRACT FROM AUTHOR]