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Applying an Inducible Expression System to Study Interference of Bacterial Virulence Factors with Intracellular Signaling
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Una cinasa Ser/Thr parecida a la de los eucariotas señala a las bacterias para que salgan de la latencia en respuesta
Ishita M Shah1, Maria-Halima Laaberki, David L Popham
1Department of Microbiology, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA.
Cell
|November 6, 2008
Resumen
Las esporas de Bacillus subtilis en estado latente pueden ser activadas para germinar por muropéptidos liberados por bacterias en crecimiento. Una quinasa específica es esencial para este proceso, ofreciendo un nuevo objetivo para el desarrollo antimicrobiano.
Área de la Ciencia:
- Microbiología Microbiología.
- Fisiología bacteriana fisiología bacteriana.
- Germinación de las esporas Germinación de las esporas
Sus antecedentes:
- Las bacterias entran en estado de latencia para sobrevivir en condiciones adversas, lo que requiere señales ambientales para reanudar el crecimiento.
- El crecimiento bacteriano es a menudo señalado por la liberación de fragmentos de pared celular (muropéptidos).
Objetivo del estudio:
- Para investigar el papel de los muropéptidos en la germinación de las esporas de Bacillus subtilis latentes.
- Identificar los mecanismos moleculares y los factores del huésped involucrados en la germinación de esporas inducida por muropéptido.
Principales métodos:
- Tratamiento de las esporas de Bacillus subtilis latentes con muropéptidos.
- Análisis genético para identificar los factores esenciales del huésped.
- Ensayos bioquímicos que utilizan pequeñas moléculas para modular la actividad de la quinasa.
Principales resultados:
- Los muropéptidos son potentes germinantes para las esporas latentes de Bacillus subtilis.
- Una quinasa de membrana Ser/Thr de tipo eucariótico con un dominio extracelular de unión de peptidoglicanos es crucial para la detección de los muropéptidos.
- Pequeñas moléculas específicas pueden inducir o inhibir la germinación de esporas dependientes de los muropéptidos.
Conclusiones:
- La germinación de esporas bacterianas puede desencadenarse mediante la detección de la presencia de otras bacterias en crecimiento a través de muropéptidos.
- La quinasa identificada representa un nuevo objetivo para el desarrollo de antimicrobianos que inhiben específicamente la germinación de esporas, a diferencia de los antibióticos tradicionales.
- La estaurosporina inhibe la germinación de esporas al bloquear esta quinasa, lo que sugiere una nueva estrategia contra las formas bacterianas latentes.
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