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Synthesis of Cationized Magnetoferritin for Ultra-fast Magnetization of Cells
Published on: December 13, 2016
Definición espectroscópica del sitio de la ferroxidasa en la ferritina M: comparación del sustrato binuclear frente a
Jennifer K Schwartz1, Xiaofeng S Liu, Takehiko Tosha
1Department of Chemistry, Stanford University, 333 Campus Drive, Stanford, California 94305, USA.
Journal of the American Chemical Society
|June 26, 2008
Resumen
Las maxiferritinas son nanojaulas de proteínas esenciales para el almacenamiento del hierro. Este estudio revela que las ranas tienen M ferritina.
Área de la Ciencia:
- La bioquímica es la bioquímica.
- Biología Estructural Biología estructural.
- La biofísica es la biofísica.
Sus antecedentes:
- Las maxiferritinas son nanojaulas de proteínas de 24 subunidades cruciales para la homeostasis del hierro en diversos organismos.
- El hierro se almacena como óxido férrico hidratado, evitando el daño de los radicales libres y la utilización de patógenos.
- La biomineralización del hierro se cataliza en un sitio activo de un sustrato biferroso no hemo.
Objetivo del estudio:
- Para investigar la unión de Fe (II) al sitio activo del sustrato en la rana M ferritina.
- Para aclarar las propiedades estructurales y electrónicas del sitio activo biferroso.
- Comprender el mecanismo de control de la absorción de hierro en la ferritina.
Principales métodos:
- Espectroscopia de dicroísmo circular (CD). espectroscopía de dicroísmo circular (CD). espectroscopía de dicroísmo circular (CD). espectroscopía de dicroísmo circular (CD). espectroscopía de dicroísmo circular (CD). espectroscopía de dicroísmo circular (CD). espectroscopía de dicroísmo circular (CD).
- Espectroscopia de dicroísmo magnético circular (MCD, por sus siglas en inglés).
- MCD de temperatura variable y campo variable (MCD VTVH) para la detección de la unión de Fe (II).
Principales resultados:
- Identificó dos centros ferrosos de cinco coordenadas (5C) no equivalentes en el sitio activo.
- Determinación de un acoplamiento antiferromagnético débil entre los centros de Fe (II), puenteado por un carboxilato mu-1,3 .
- Observaciones concertadas de enlace y cooperación entre los sitios activos dentro de cada subunidad.
- Caracterizó un conjunto inusual de ligandos del sitio activo que incluye moléculas terminales de agua.
Conclusiones:
- La estructura del sitio activo de la ferritina M de la rana difiere de otras enzimas biferrosas.
- La vinculación y la cooperación concertadas sugieren un mecanismo para regular la carga de hierro en la ferritina.
- Las características estructurales únicas influyen en las funciones catalíticas y de almacenamiento de hierro de la ferritina.
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