Type II secretion system of Pseudomonas aeruginosa: in vivo evidence of a significant role in death due to lung infection.
J Infect Dis
; 203(10): 1369-77, 2011 May 15.
Article
en En
| MEDLINE
| ID: mdl-21502078
ABSTRACT
BACKGROUND:
The role of toxins secreted by the type II secretion system (T2SS) of Pseudomonas aeruginosa during lung infection has been uncertain despite decades of research.METHODS:
Using a model of pneumonia in Toll-like receptor (TLR) 2,4(-/-) mice, we reexamined the role of the T2SS system. Flagellin-deficient mutants of P. aeruginosa, with mutations in the T2SS and/or T3SS, were used to infect mice. Mice were followed up for survival, with some killed at different intervals to study bacterial clearance, inflammatory responses, and lung pathology.RESULTS:
Strains carrying either secretion system were lethal for mice. Double mutants were avirulent. The T3SS(+) strains killed mice within a day, and the T2SS(+) strains killed them later. Mice infected with a strain that had only the T2SS were unable to eradicate the organism from the lungs, whereas those infected with a T2SS-T3SS double deletion were able to clear this mutant. Death caused by the T2SS(+) strain was accompanied by a >50-fold increase in bacterial counts and higher numbers of viable intracellular bacteria.CONCLUSIONS:
The T2SS of P. aeruginosa may play a role in death from pneumonia, but its action is delayed. These data suggest that antitoxin strategies against this organism will require measures against the toxins secreted by both T2SS and T3SS.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Pseudomonas aeruginosa
/
Infecciones por Pseudomonas
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Toxinas Bacterianas
/
Neumonía Bacteriana
Tipo de estudio:
Prognostic_studies
Límite:
Animals
Idioma:
En
Revista:
J Infect Dis
Año:
2011
Tipo del documento:
Article
País de afiliación:
Estados Unidos