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La formación de fibras a través de la membrana externa bacteriana por la vía de acompañante / huésped
Han Remaut1, Chunyan Tang, Nadine S Henderson
1Institute of Structural Molecular Biology, University College London and Birkbeck College, Malet Street, London, WC1E 7HX, United Kingdom.
Cell
|May 20, 2008
Resumen
Las bacterias gramnegativas utilizan las vías de chaperón / usher para construir pili adhesivos para la fijación del huésped. Los estudios estructurales revelan el usher.
Área de la Ciencia:
- Microbiología Microbiología.
- Biología Estructural Biología estructural.
- La bioquímica es la bioquímica.
Sus antecedentes:
- Las bacterias gramnegativas utilizan pili adhesivo para la colonización del huésped.
- El ensamblaje de pili está mediado principalmente por la vía de acompañante / huésped.
- Comprender esta vía es crucial para desarrollar estrategias antimicrobianas.
Objetivo del estudio:
- Aclarar los mecanismos estructurales del ensamblaje y la secreción de pilus.
- Para caracterizar el papel del acomodador en la translocación de la membrana externa.
Principales métodos:
- Determinación de la estructura cristalina del dominio de translocación P pilus usher PapC.
- Microscopía crioectrónica de partículas únicas del FimD usher con un intermediario pilus.
Principales resultados:
- Reveló la arquitectura molecular del acomodador como una maquinaria de translocación de poro gemelado.
- Se ha demostrado que sólo un poro se utiliza para la secreción pilus.
- Identificó las funciones duales para los protómeros usher en el reclutamiento complejo de chaperona-subunidad.
- Caracterizó la estructura de los poros, incluido un dominio de enchufe y una puerta de horquilla beta.
Conclusiones:
- El estudio proporciona conocimientos estructurales sin precedentes en la vía de acompañante / huésped.
- Estos hallazgos iluminan el mecanismo de secreción del factor de virulencia a través de la membrana externa bacteriana.
- Las estructuras detalladas ofrecen objetivos potenciales para nuevas terapias antibacterianas.
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