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Efectos del disolvente antihidrofóbico: una sonda experimental para la contribución hidrofóbica a la unión del
Paul A Bartlett1, Naeem Yusuff, Alice C Rico
1Department of Chemistry, University of California, Berkeley, California 94720-1460, USA. paul@fire.cchem.berkeley.edu
Journal of the American Chemical Society
|April 11, 2002
Resumen
Este estudio investigó el efecto hidrofóbico en la unión de inhibidores de enzimas utilizando diferentes composiciones de disolventes. Los resultados muestran que el aumento de la concentración de etanol mejora significativamente la afinidad de unión, ofreciendo información sobre las interacciones proteína-ligando.
Área de la Ciencia:
- La bioquímica es la bioquímica.
- Biología Química Biología química.
- La cinética de las enzimas.
Sus antecedentes:
- Comprender las interacciones proteína-ligando es crucial en el descubrimiento de fármacos.
- El efecto hidrofóbico juega un papel importante en la unión molecular.
- La termolisina es una peptidasa de zinc relevante para los procesos biológicos.
Objetivo del estudio:
- Para cuantificar la contribución hidrofóbica a la afinidad de unión de los inhibidores de fosfinato y fosfonamidato con la termolisina.
- Desarrollar un método experimental para diferenciar los efectos de solvación de otras influencias de unión.
- Para correlacionar el efecto hidrofóbico observado con la superficie hidrofóbica secuestrada.
Principales métodos:
- Se han investigado las afinidades de unión de los inhibidores de la termolisina a través de diferentes composiciones de disolventes tampón de etanol (0-9% de etanol).
- Constantes de inhibición medidas (K(i)) para evaluar la fuerza de unión.
- Analizó la relación entre la composición del disolvente y la afinidad de unión.
Principales resultados:
- El aumento de la concentración de etanol en la solución tampón condujo a un aumento de las constantes de inhibición (K ((i)) hasta un orden de magnitud.
- La magnitud del "efecto antihidrofóbico" se correlacionó con el área de superficie hidrofóbica enterrada en la asociación inhibidor-enzima.
- Los efectos observados se atenuaron en comparación con las predicciones basadas en la tensión superficial de la mezcla de etanol y agua.
Conclusiones:
- El estudio proporciona un enfoque experimental para diseccionar los efectos de solvación en la unión proteína-ligando.
- Los resultados apoyan la teoría de Lum-Chandler-Weeks con respecto a la dependencia de tamaño del efecto hidrofóbico.
- Las interacciones hidrofóbicas influyen significativamente en la afinidad de unión de los inhibidores a la termolisina.
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