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La estructura de una proteína determinada por la espectroscopia de RMN de ángulo giratorio mágico en estado sólido
Federica Castellani1, Barth van Rossum, Annette Diehl
1Forschungsinstitut für Molekulare Pharmakologie, Robert-Rössle-Strasse 10, 13125 Berlin, Germany.
Nature
|November 8, 2002
Resumen
La resonancia magnética nuclear de estado sólido (RMN) determinó la estructura del dominio SH3 del espectro alfa. Este método es valioso para las proteínas difíciles de cristalizar, como las proteínas de membrana.
Área de la Ciencia:
- La biofísica es la biofísica.
- Biología Estructural Biología estructural.
- Espectroscopia de resonancia magnética nuclear Espectroscopia de resonancia magnética nuclear Espectroscopia de resonancia magnética nuclear Espectroscopia de resonancia magnética nuclear
Sus antecedentes:
- La determinación de las estructuras de las proteínas es esencial en la genómica estructural.
- La RMN en estado sólido es crucial para las proteínas que resisten la cristalización o la RMN en solución, incluidos los sistemas amiloides y las proteínas de membrana.
- Este estudio se centra en el dominio 3 (SH3) de la homología Src del espectro alfa.
Objetivo del estudio:
- Para presentar una estructura proteica determinada mediante la RMN de estado sólido de giro de ángulo mágico (MAS).
- Demostrar la aplicabilidad de la RMN en estado sólido para la determinación estructural de objetivos proteicos difíciles.
- Establecer un método aplicable a las pequeñas proteínas de membrana expresadas en bacterias.
Principales métodos:
- Se empleó RMN de estado sólido de giro mágico de ángulo (MAS) para la determinación estructural.
- Se obtuvieron asignaciones de resonancia completas de carbono-13 ((13) C) y nitrógeno-15 ((15) N) para el dominio SH3 del espectro alfa microcristalino.
- Las restricciones de distancia se derivaron de los espectros de difusión de espín impulsada por protones (PDSD) de muestras etiquetadas dirigidas al sitio.
Principales resultados:
- Se calculó un pliegue global del dominio SH3 del espectro alfa.
- La determinación de la estructura se basó en 286 entre-residuos (13) C-(13) C y seis (15) N-(15) N restricciones.
- Se observaron correlaciones de distancia de largo alcance hasta aproximadamente 7 Å.
Conclusiones:
- La RMN MAS de estado sólido determinó con éxito la estructura del dominio SH3 del espectro alfa.
- La metodología permite la observación de restricciones de distancia de largo alcance.
- Este enfoque de RMN MAS es potencialmente ampliamente aplicable a las pequeñas proteínas de membrana expresadas en bacterias.
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