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Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
La quiralidad de las superestructuras amiloides
Noa Rubin1, Emanuel Perugia, Michal Goldschmidt
1Department of Structural Biology, Weizmann Institute of Science, Rehovot, Israel 76100.
Journal of the American Chemical Society
|March 15, 2008
Resumen
Las fibrillas amiloides exhiben estructuras helicoidales distintas. Los investigadores descubrieron que mientras que la mayoría de los amiloides forman hélices zurdas, los péptidos de amiloide A séricos crean hélices derechistas, revelando que la organización estructural influye en la quiralidad.
Área de la Ciencia:
- La bioquímica es la bioquímica.
- Biología Estructural Biología estructural.
- La biofísica es la biofísica.
Sus antecedentes:
- Las amiloides son agregados de proteínas vinculados a más de 20 enfermedades.
- Las fibras amiloides poseen una estructura beta cruzada característica que forma superestructuras helicoidales.
Objetivo del estudio:
- Para investigar la quiralidad de las superestructuras amiloides utilizando microscopía de alta resolución.
- Para determinar si la quiralidad molecular dicta la organización helicoidal supramolecular en los amiloides.
Principales métodos:
- Microscopía electrónica de barrido de alta resolución (SEM).
- Microscopía electrónica de crioscáner (Cryo-SEM).
Principales resultados:
- Las amiloides de Abeta1-40 y la lisozima de hen forman exclusivamente hélices zurdas.
- Los péptidos de amiloide A (SAA1-12) en suero forman exclusivamente hélices derechistas.
- Los enantiómeros del péptido ((R) -aminoácidos) se agregan en hélices zurdas.
Conclusiones:
- La destreza de los amiloides SAA1-12 es una característica intrínseca del péptido.
- Las hélices de la izquierda se alinean con el modelo convencional de hoja beta.
- Las hélices SAA1-12 de la mano derecha sugieren que su estructura beta cruzada puede no incluir hojas beta, destacando el papel de la organización estructural en la quiralidad supramolecular.
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