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La detección de Fucose regula la colonización intestinal de las bacterias
Alline R Pacheco1, Meredith M Curtis, Jennifer M Ritchie
1Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9048, USA.
Nature
|November 20, 2012
Resumen
La Escherichia coli enterohemorrágica (EHEC) utiliza fucosa, un azúcar abundante en el intestino, para controlar su virulencia. Este sistema de detección de fucosa, FusKR, es crucial para la colonización de EHEC y la patogenicidad en el intestino de los mamíferos.
Área de la Ciencia:
- Microbiología Microbiología.
- Biología Molecular Biología Molecular
- Gastroenterología y Gastroenterología.
Sus antecedentes:
- El intestino de los mamíferos es un entorno microbiano competitivo.
- La colonización de patógenos requiere la eliminación de nutrientes, la detección de señales y la regulación del gen de virulencia.
- La Escherichia coli enterohemorrágica (EHEC) utiliza la señalización entre reinos para la virulencia.
Objetivo del estudio:
- Identificar nuevos sistemas de detección de sustancias químicas en el EHEC.
- Investigar el papel de la detección de fucosa en la virulencia y colonización de la EHEC.
- Para aclarar la interacción entre la microbiota y la EHEC en el intestino.
Principales métodos:
- Caracterización de un nuevo sistema de dos componentes, llamado FusKR (FusK sensor kinase, regulador de respuesta FusR).
- Análisis de las capacidades de detección de fucose de FusK.
- Evaluación del requisito del sistema FusKR para la colonización intestinal EHEC.
- Investigando el papel de Bacteroides thetaiotaomicron en la activación de la virulencia EHEC a través de la fucosa.
Principales resultados:
- Un nuevo sistema de dos componentes de detección de fucosa, FusKR, fue identificado en EHEC.
- FusKR controla la expresión de los genes de virulencia y metabólicos.
- El sistema FusKR es esencial para una robusta colonización EHEC del intestino de los mamíferos.
- Bacteroides thetaiotaomicron divide la fucosa de la mucina, activando el sistema FusKR de EHEC y modulando la expresión génica de la virulencia.
Conclusiones:
- EHEC emplea el sistema FusKR para detectar y utilizar fucosa, un nutriente fácilmente disponible en el intestino.
- La disponibilidad de fucosa impulsada por la microbiota influye en la patogenicidad y el metabolismo de la EHEC.
- Este estudio revela un mecanismo por el cual el EHEC se adapta al entorno del huésped mediante la detección de señales derivadas del huésped disponibles por bacterias comensales.
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