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Arquitectura molecular in situ de la máquina de secreción de Salmonella tipo III
Bo Hu1, Maria Lara-Tejero2, Qingke Kong3
1Department of Pathology and Laboratory Medicine, University of Texas Medical School at Houston, Houston, TX 77030, USA.
Cell
|March 12, 2017
Resumen
Este estudio revela la estructura de alta resolución de la máquina de secreción de Salmonella Typhimurium tipo III in situ. Comprender este sistema de secreción bacteriana
Área de la Ciencia:
- Microbiología
- Biología estructural
- Biología celular
Sus antecedentes:
- Los sistemas de secreción de tipo III (T3SS) son factores de virulencia esenciales en muchos patógenos bacterianos.
- Estas máquinas moleculares complejas entregan proteínas efectoras bacterianas directamente a las células eucariotas huésped.
- El T3SS comprende un complejo de agujas, un aparato de exportación de membrana interna y una plataforma de clasificación citoplasmática.
Objetivo del estudio:
- Determinar la estructura in situ de alta resolución de la Salmonella Typhimurium T3SS.
- Para aclarar la arquitectura molecular y la localización de los componentes de la T3SS.
- Comprender el mecanismo de ensamblaje y los cambios conformacionales durante la formación de T3SS.
Principales métodos:
- Tomografía criolectrónica de alto rendimiento (Crio-ET).
- El promedio del subtomograma.
- Modelado molecular y análisis comparativo de mutantes de deleción y componentes etiquetados con proteínas.
Principales resultados:
- Se obtuvo una estructura in situ de alta resolución de Salmonella Typhimurium T3SS.
- Se determinó la arquitectura molecular y la localización de los componentes de T3SS.
- El acoplamiento de la plataforma de clasificación induce cambios de conformación en el complejo de agujas, lo que permite el montaje.
Conclusiones:
- El estudio proporciona información estructural sin precedentes sobre la máquina T3SS.
- Este trabajo aclara el proceso de ensamblaje y la dinámica estructural de este sistema crítico de secreción bacteriana.
- Los hallazgos avanzan en nuestra comprensión de la patogénesis bacteriana y las interacciones huésped-patógeno.
Palabras clave:
Patogénesis de las salmonelasPatogénesis bacterianaTomografía cryoelectrónicaMáquinas molecularessecreción de proteínasMás Videos Relacionados
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