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Imaging InlC Secretion to Investigate Cellular Infection by the Bacterial Pathogen Listeria monocytogenes
Published on: September 19, 2013
Una secuencia similar a PEST en listeriolisina O es esencial para la patogenicidad de Listeria monocytogenes
1Department of Molecular and Cell Biology, Division of Infectious Diseases, School of Public Health, University of California, Berkeley, CA 94720, USA.
Science (New York, N.Y.)
|November 4, 2000
Resumen
Una secuencia similar a la PEST en Listeria monocytogenes listeriolysin O (LLO) es crucial para la virulencia del patógeno. Esta secuencia apunta a LLO para la degradación, evitando el daño de las células huésped y permitiendo la supervivencia intracelular.
Área de la Ciencia:
- Microbiología Microbiología.
- Biología celular Biología celular.
- Interacciones Patógeno-Huésped Interacciones Patógeno-Huésped
Sus antecedentes:
- Los patógenos intracelulares requieren un nicho protegido para la supervivencia y la replicación dentro de las células huésped.
- Listeria monocytogenes utiliza la proteína formadora de poros listeriolysin O (LLO) durante su ciclo de infección.
Objetivo del estudio:
- Investigar el papel de una secuencia similar a PEST en la función de LLO, la virulencia y la compartimentación intracelular.
- Para determinar el impacto de esta secuencia en la interacción de LLO con las células huésped.
Principales métodos:
- Mutagénesis dirigida al sitio para crear mutantes LLO que carecen de la secuencia similar a la PEST.
- Análisis de la entrada de bacterias en las células huésped y su posterior destino intracelular.
- Evaluación de la viabilidad e integridad de la célula huésped.
- Transferencia funcional de la secuencia similar a la PEST a otra citolisina, la perfringolisina O.
Principales resultados:
- Los mutantes LLO que carecen de la secuencia similar a la PEST entraron en el citosol del huésped, pero causaron la permeabilización y muerte de la célula huésped.
- LLO que carece de la secuencia similar a PEST se acumula en el citosol del huésped, lo que indica que se dirige a LLO para la degradación.
- La transferencia de la secuencia similar a la PEST a la perfringolisina O la hizo no tóxica y promovió el crecimiento intracelular.
Conclusiones:
- La secuencia similar a la PEST en LLO es esencial para la virulencia de Listeria monocytogenes y la adecuada compartimentación intracelular.
- Esta secuencia media la degradación de LLO, impidiendo la lisis prematura de las células huésped y facilitando la supervivencia del patógeno.
- La secuencia similar a la PEST se puede transferir funcionalmente a otras citolisinas para modular su toxicidad y promover el crecimiento intracelular.
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