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Novobiocin mejora la actividad de la polimixina al estimular el transporte de lipopolisacáridos
Michael D Mandler1, Vadim Baidin1, James Lee1
1Department of Chemistry and Chemical Biology , Harvard University , Cambridge , Massachusetts 02138 , United States.
Journal of the American Chemical Society
|May 11, 2018
Resumen
Derivados de la novobiocina dirigidos al transporte de lipopolisacáridos (LPS) que mejoran la polimixina
Área de la Ciencia:
- Microbiología
- Descubrimiento de drogas
- La bioquímica
Sus antecedentes:
- Las bacterias gramnegativas poseen una membrana externa desafiante que dificulta la eficacia de los antibióticos.
- Las polimixinas como la colistina son antibióticos de último recurso pero presentan toxicidad.
- La novobiocina actúa en sinergia con la polimixina ayudando a la penetración en la membrana externa.
Objetivo del estudio:
- Sintetizar y evaluar los derivados de la novobiocina con actividades distintas.
- Investigar el papel de la estimulación de LptB en la sinergia entre la polimixina y la novobiocina.
- Desarrollar terapias de combinación mejoradas para las infecciones Gram negativas.
Principales métodos:
- Síntesis de nuevos análogos de la novobiocina.
- Ensayos para separar la inhibición de la ADN girasa y la estimulación de LptB.
- Evaluación de la letalidad sinérgica con la polimixina.
Principales resultados:
- Un análogo de la novobiocina que estimula la LptB pero no inhibe la ADN girasa aumentó la letalidad de la polimixina.
- Esto indica que el agonismo del transporte de lipopolisacáridos (LPS) contribuye significativamente a la sinergia.
- Otros análogos con mayor unión a LptB mostraron mayor potencia con la polimixina.
Conclusiones:
- La estimulación del transporte de LPS es un mecanismo clave para la sinergia entre la novobiocina y la polimixina.
- Los análogos de novobiocina optimizados pueden mejorar la eficacia y la seguridad de la polimixina.
- Dirigirse al transporte de LPS ofrece una estrategia prometedora contra las bacterias Gram-negativas.
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