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Actuación alostérica de la transición de fase inversa de un polipéptido de fusión sensible al estímulo por unión de
Bumjoon Kim1, Ashutosh Chilkoti
1Department of Biomedical Engineering, Duke University, Durham, North Carolina 27708-0281, USA.
Journal of the American Chemical Society
|December 6, 2008
Resumen
Desarrollamos un nuevo actuador de biopolímeros que utiliza la unión de ligandos para controlar las transiciones de fase del polímero. Esta innovación permite que los materiales inteligentes que responden a las señales biológicas para aplicaciones en la administración de medicamentos y diagnósticos.
Área de la Ciencia:
- Ciencia de los Biomateriales Ciencia de los Biomateriales.
- Química de Polímeros La Química de Polímeros es la química de los polímeros.
- Ingeniería Molecular Ingeniería Molecular
Sus antecedentes:
- Los polímeros sensibles al estímulo, como los polipéptidos similares a la elastina (ELPs), exhiben transiciones de fase sintonizables.
- El control de estas transiciones de fase con desencadenantes bioquímicos específicos sigue siendo un desafío.
Objetivo del estudio:
- Diseñar un actuador de biopolímero que vincule la unión de ligando a una transición de fase de desmixado acuoso.
- Para demostrar la regulación alostérica del polipéptido similar a la elastina (ELP) las transiciones de fase a la temperatura crítica de solución más baja (LCST) a través del reconocimiento biomolecular.
Principales métodos:
- Se construyó un actuador modular de biopolímeros mediante la fusión de calmodulina (CaM) con un dominio ELP.
- Investigó la unión del calcio al CaM y su efecto en el comportamiento de la transición de fase del ELP.
- Evaluó la reversibilidad, selectividad y especificidad del sistema CaM-ELP.
Principales resultados:
- La unión del calcio al CaM alostéricamente desencadenó la transición de fase LCST reversible del ELP, formando partículas.
- La formación de partículas dependía de la longitud de la cadena ELP y era reversible con la quelación de calcio.
- El sistema demostró selectividad para el calcio sobre el magnesio y especificidad contra un ligando peptídico.
Conclusiones:
- Logró la primera demostración de la regulación alostérica desencadenada por el reconocimiento biomolecular de las transiciones de fase LCST de polímeros.
- Amplió el rango de desencadenantes para polímeros que responden al estímulo para incluir la unión de ligandos bioquímicos.
- Este diseño modular ofrece potencial para actuadores de polímero "inteligentes" en la administración de fármacos, proteómica y dispositivos a nanoescala.
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