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El peptidoglicano controla la maduración del conjunto de proteínas de la membrana externa
Gideon Mamou1, Federico Corona2,3, Ruth Cohen-Khait1
1Department of Biochemistry, South Parks Road, University of Oxford, Oxford, UK.
Nature
|June 15, 2022
Resumen
La estructura de los peptidoglicanos en las bacterias gramnegativas guía la inserción de proteínas de la membrana externa (OMP). El peptidoglicano maduro limita la inserción de OMP, asegurando que los OMP se insertan preferentemente en los sitios de división durante el crecimiento celular.
Área de la Ciencia:
- Microbiología
- Biología celular
- La bioquímica
Sus antecedentes:
- Las proteínas de la membrana externa (OMP) son esenciales para la función e integridad de la membrana externa de las bacterias Gram-negativas.
- El complejo de la máquina de ensamblaje β-barril (BAM) es responsable de la inserción de las OMP en la membrana externa.
- El mecanismo detrás de la segregación polar observada de los PMO en Escherichia coli en crecimiento sigue sin estar claro.
Objetivo del estudio:
- Investigar el papel del peptidoglicano en la organización espacio-temporal de las proteínas de la membrana externa (OMP) en bacterias Gram negativas.
- Para aclarar cómo la maduración del peptidoglicano influye en la biogénesis y la inserción de OMP.
- Para entender la base de la partición binaria OMP durante la división celular.
Principales métodos:
- Se investigó la interacción entre los componentes de peptidoglicano y BAM mediante ensayos bioquímicos.
- Se evaluó el efecto de los diferentes estados de maduración del peptidoglicano en la actividad de la OMP foldasa.
- Utilizó microscopía y enfoques genéticos para rastrear la localización e inserción de OMP durante la división celular.
Principales resultados:
- El peptidoglicano maduro se une a los componentes de BAM e inhibe la actividad de la foldasa OMP.
- El peptidoglicano naciente, que se encuentra en el septa, interactúa débilmente con el BAM y exhibe un efecto inhibidor mínimo.
- Esta interacción diferencial conduce a la inserción preferente de nuevos OMP en los sitios de división celular, lo que explica la partición binaria.
Conclusiones:
- La maduración del peptidoglicano es un regulador clave de la biogénesis y localización de las proteínas de la membrana externa en las bacterias Gram negativas.
- La coordinación entre la síntesis de la pared celular y la inserción de OMP garantiza el correcto ensamblaje y la integridad de la envoltura celular.
- Este mecanismo regulador representa un objetivo potencial para el desarrollo de nuevos antibióticos.
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