El chaperone priming de las subunidades pilus facilita una transición topológica que impulsa la formación de fibras
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Published on: June 12, 2015
Frederic G Sauer1, Jerome S Pinkner, Gabriel Waksman
1Department of Molecular Microbiology, Washington University Medical School, 660 South Euclid Avenue, St. Louis, MO 63105, USA.
Cell
|November 20, 2002
Resumen
El ensamblaje del pilus bacteriano se basa en las chaperonas periplásmicas. Estas chaperones son las subunidades principales para la formación de fibra a través de un mecanismo de intercambio de hebras donantes, lo que permite la patogénesis bacteriana.
Área de la Ciencia:
- Microbiología Microbiología.
- Biología Estructural Biología estructural.
- La bioquímica es la bioquímica.
Sus antecedentes:
- Las chaperonas periplásmicas son esenciales para la construcción de fibras pilus multi-subunidad en las bacterias.
- Las fibras pilus son cruciales para la patogénesis y la adhesión bacteriana.
- El ensamblaje de Pilus implica un mecanismo de intercambio de hebras donantes entre las subunidades.
Objetivo del estudio:
- Para dilucidar el papel de las chaperonas periplásmicas en la preparación de las subunidades bacterianas para el ensamblaje del pilar.
- Investigar el mecanismo de intercambio de hebras donantes y su regulación.
- Para entender cómo la acción de la chaperona impulsa la incorporación de subunidades en las fibras pilus.
Principales métodos:
- Análisis estructural de las interacciones chaperona-subunidad.
- Análisis bioquímicos para monitorear el intercambio de hebras de donantes.
- Estudios de conformación de las subunidades durante el montaje.
Principales resultados:
- Las chaperonas periplásmicas mantienen la ranura de la subunidad en un estado abierto y activado.
- El intercambio de hebras donantes induce una transición topológica en la subunidad.
- Esta transición conduce al cierre de ranura, sellando la subunidad ensamblada en la fibra pilus.
Conclusiones:
- El encofrado de Chaperone es crítico para activar la conformación lista para ensamblar de la subunidad.
- La transición topológica durante el intercambio de hebras donantes es la fuerza motriz clave para el alargamiento del pilar.
- Comprender este mecanismo proporciona información sobre la adhesión bacteriana y la patogénesis.
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