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Synthesis and Characterization of Supramolecular Colloids
Published on: April 22, 2016
Investigación de interacciones no covalentes en péptidos desprotonados: competencia estructural y energética entre la
Dengfeng Liu1, Thomas Wyttenbach, Catherine J Carpenter
1Department of Chemistry and Biochemistry, University of California at Santa Barbara, California 93106, USA.
Journal of the American Chemical Society
|March 12, 2004
Resumen
Este estudio utilizó espectrometría de masas y métodos computacionales para investigar las interacciones no covalentes en pequeños sistemas de péptidos. Los resultados muestran que el agua y los péptidos neutros disuelven los péptidos desprotonados de manera similar, con implicaciones para la comprensión de la agregación y disolución de péptidos.
Área de la Ciencia:
- Química analítica Química analítica es la que
- Química computacional es la química computacional.
- Química Física es la química física.
Sus antecedentes:
- Las interacciones no covalentes gobiernan la estructura y la función del péptido.
- Comprender la disolución de péptidos es crucial para los procesos biológicos.
- La espectrometría de masas por electrospray es una herramienta poderosa para el estudio de complejos no covalentes.
Objetivo del estudio:
- Examinar las interacciones no covalentes péptido-péptido y péptido-agua en sistemas modelo.
- Para comparar las capacidades de disolución del agua y los péptidos neutros para los péptidos desprotonados.
- Para determinar las energías de unión y las energías de activación para la agregación y disociación de péptidos.
Principales métodos:
- Espectrometría de masas por electrospray con una célula de deriva de alta presión.
- Cálculos de mecánica molecular (MM) y teoría funcional de la densidad (DFT).
- Equilibrio de hidratación dependiente de la temperatura y experimentos de cinética.
Principales resultados:
- Los péptidos de dialanina (AA) y diglicina (GG) forman iones dímeros en el electrospray.
- Las energías de unión al agua oscilaron entre 11,7 y 7,1 kcal/mol para [AA-H](-) y entre 11,0 y 7,4 kcal/mol para [GG-H](-).
- Cuatro moléculas de agua proporcionan una solución similar a un péptido neutro para un péptido desprotonado.
- Las energías de activación para la disociación del dímero fueron de 34,9 kcal/mol para [AA-H](-). (AA) y 32,2 kcal/mol para [GG-H] (GG).- Se trata de un proyecto de ley.
Conclusiones:
- Las interacciones péptido-agua y péptido-péptido son comparables en la solvatación de péptidos desprotonados.
- Los métodos computacionales y experimentales proporcionan una visión consistente de la agregación de péptidos.
- Los hallazgos contribuyen a comprender las fuerzas fundamentales que impulsan el ensamblaje de péptidos.
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