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La densidad de las micelas regulada por un cambio reversible de la estructura secundaria de la proteína
Rory E Sallach1, Min Wei, Nilanjana Biswas
1Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA.
Journal of the American Chemical Society
|September 7, 2006
Resumen
Los investigadores diseñaron micelas de proteínas inteligentes que cambian de tamaño y densidad con la temperatura. Esta transición de plegamiento de proteínas ofrece un nuevo enfoque para los sistemas de administración de fármacos sensibles a estímulos.
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 de proteínas Ingeniería de proteínas.
Sus antecedentes:
- Las estructuras secundarias de las proteínas pueden sufrir transiciones abruptas y reversibles.
- Tales transiciones pueden aprovecharse para diseñar materiales receptivos.
- Los copolímeros proteicos anfifílicos ofrecen potencial para el autoensamblaje en nanoestructuras.
Objetivo del estudio:
- Diseñar y caracterizar un sistema micelar "inteligente" de proteínas utilizando secuencias de péptidos elastin-miméticos.
- Para investigar el efecto del plegamiento de proteínas inducido por la temperatura en las propiedades de la micela.
- Establecer un nuevo mecanismo para los vehículos de administración de drogas sensibles a los estímulos.
Principales métodos:
- Utilizó métodos de ADN recombinante para preparar un copolímero de proteína tribloqueante.
- Investigación de la formación de micelas y propiedades en soluciones diluidas por debajo y por encima de la temperatura de transición inversa (Tt).
- Se analizaron los cambios en la compacidad y el tamaño de las micelas utilizando técnicas biofísicas.
Principales resultados:
- Copolímeros de tribloqueo de proteínas anfifílicas desarrollados que forman micelas monodispersas (~100 nm R(H)) por debajo de Tt.
- Se observó un aumento abrupto en la densidad interna de la micela y un tamaño reducido por encima de Tt.
- Se demostró que el cambio estructural es impulsado por una transición de plegamiento de proteínas de hélice a hoja.
Conclusiones:
- Las transiciones de la estructura secundaria de las proteínas se pueden utilizar de manera controlable para diseñar sistemas micelares "inteligentes".
- El plegamiento de proteínas inducido por la temperatura altera de manera reversible la compacidad y el tamaño de la micela.
- Estas micelas basadas en polímeros de proteínas representan una nueva plataforma para aplicaciones avanzadas de administración de fármacos.
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