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El factor de hibernación ribosomal vincula la detección de quórum con la resistencia al ácido en la EHEC
Yang Yang1,2, Xinyi Zhang3, Zixin Han1,2
1College of Veterinary Medicine, Yangzhou University, Yangzhou 225009, China.
Microorganisms
|August 28, 2025
Resumen
La detección de quórum (QS) mejora la resistencia al estrés de la Escherichia coli (E. coli) enterohemorrágica O157: H7 mediante la activación de la hibernación ribosómica. Este mecanismo, mediado por el eje SdiA-RMF-RpoS, aumenta la supervivencia del patógeno frente a diversas tensiones.
Área de la Ciencia:
- Microbiología
- Biología molecular
- Investigación de patógenos
Sus antecedentes:
- La Escherichia coli enterohemorrágica (EHEC) O157:H7 plantea amenazas significativas transmitidas por los alimentos.
- Los mecanismos subyacentes a la resistencia al estrés mediada por la detección de quórum (QS) en EHEC no se comprenden completamente.
Objetivo del estudio:
- Para aclarar el papel de QS en la mejora de la resistencia al estrés ácido en EHEC O157:H7.
- Identificar los actores moleculares clave y las vías involucradas en la resiliencia al estrés mediada por QS.
Principales métodos:
- Se utilizaron las N-acil-homoserinelactonas (AHLs) exógenas optimizadas y las AHLs endógenas para inducir QS en EHEC O157:H7.
- Empleó la transcriptómica de ARN-seq para identificar genes expresados diferencialmente.
- Mutantes knockout isogénicos generados y analizados.
- Se realizaron ensayos de qRT-PCR y de supervivencia al estrés para validar los mecanismos moleculares.
Principales resultados:
- QS mejoró significativamente la resistencia EHEC O157: H7 al estrés ácido.
- El RNA-seq identificó la regulación al alza del gen RMF.
- Los mutantes knockout mostraron una resistencia al estrés abolida y una vulnerabilidad al estrés general.
- Se estableció el eje SdiA-RMF-RpoS, que vincula el QS con la latencia ribosómica y la respuesta SOS.
Conclusiones:
- La hibernación ribosómica es una estrategia adaptativa central que vincula el QS a la resiliencia del patógeno en la EHEC.
- El eje SdiA-RMF-RpoS es crucial para la supervivencia de la EHEC en diversas condiciones de estrés.
- Proporciona información mecanicista para desarrollar nuevas estrategias de control EHEC contra las enfermedades transmitidas por los alimentos.
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