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Separation of the Cell Envelope for Gram-negative Bacteria into Inner and Outer Membrane Fractions with Technical Adjustments for Acinetobacter baumannii
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Base estructural para la inserción de lipopolisacáridos en la membrana externa de las bacterias
Shuai Qiao1, Qingshan Luo1, Yan Zhao2
11] National Laboratory of Biomacromolecules, National Center of Protein Science-Beijing, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China [2] University of Chinese Academy of Sciences, Beijing 100101, China.
Nature
|July 4, 2014
Resumen
Los investigadores determinaron la estructura cristalina del complejo D-E de transporte de lipopolisacáridos (LPT) en las bacterias Gram-negativas. Esto revela una estructura única de enchufe y cañón crucial para la integridad de la membrana externa y posibles nuevos objetivos antibióticos.
Área de la Ciencia:
- Biología estructural Biología estructural.
- Microbiología Microbiología.
- La bioquímica es la bioquímica.
Sus antecedentes:
- Las membranas biológicas exhiben una distribución asimétrica de lípidos.
- Las bacterias gramnegativas utilizan lipopolisacáridos (LPS) en su membrana externa.
- Siete proteínas de transporte de lipopolisacáridos (Lpt) son esenciales para la exportación de LPS.
Objetivo del estudio:
- Para determinar la estructura cristalina del complejo LptD-LptE.
- Para dilucidar el mecanismo de inserción de LPS en la membrana externa.
- Identificar objetivos potenciales para nuevos antibióticos.
Principales métodos:
- Cristalografía de rayos X con rayos X.
- Determinación de la estructura compleja LptD-LptE a una resolución de 2.4 Å.
Principales resultados:
- La estructura reveló una nueva arquitectura de dos proteínas de enchufe y cañón.
- LptE está incrustado dentro de un barril β de 26 hebras formado por LptD.
- Los residuos de prolina en LptD crean un portal potencial para la difusión lateral de LPS.
Conclusiones:
- La estructura LptD-LptE proporciona información sobre la inserción de la membrana externa del LPS.
- Las características estructurales identificadas ofrecen nuevas vías para el desarrollo de antibióticos dirigidos a las membranas externas bacterianas.
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