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Protein Film Infrared Electrochemistry Demonstrated for Study of H2 Oxidation by a [NiFe] Hydrogenase
Published on: December 4, 2017
Reactividad de las formas peroxo del cofactor haloperoxidasa de vanadio. Una investigación sobre el DFT se encuentra
Giuseppe Zampella1, Piercarlo Fantucci, Vincent L Pecoraro
1Department of Biotechnology and Biosciences, University of Milano-Bicocca, Piazza della Scienza 2, 20126 Milan, Italy.
Journal of the American Chemical Society
|January 20, 2005
Resumen
La teoría funcional de la densidad revela que la protonación activa los complejos peroxo de las haloperoxidasas de vanadio (VHPO). El átomo de oxígeno no protonado facilita la oxo-transferencia, con Lys353 imitando la activación de protones.
Área de la Ciencia:
- La bioquímica es la bioquímica.
- Química computacional es la química computacional.
- Mecanismos de las enzimas.
Sus antecedentes:
- Las haloperoxidasas de vanadio (VHPO) son enzimas que utilizan un cofactor de peroxo-vanadio.
- Comprender la reactividad del cofactor es clave para dilucidar los mecanismos catalíticos de la VHPO.
Objetivo del estudio:
- Investigar las propiedades estructurales, electrónicas y de reactividad de los complejos peroxo VHPO.
- Examinar la influencia del estado de protonación y el microambiente en la reactividad del cofactor.
Principales métodos:
- Se emplearon cálculos de la teoría funcional de la densidad (DFT).
- El análisis se centró en modelos complejos de peroxo-vanadio.
Principales resultados:
- La protonación activa significativamente los complejos de peroxo-vanadio, alineándose con los hallazgos experimentales.
- El paso de transferencia de oxo implica un oxígeno peroxo axial accesible y no protonado.
- Se encontró que Lys353 potencialmente imita la activación de protones del cofactor peroxo.
Conclusiones:
- La protonación es crucial para activar el cofactor peroxo VHPO.
- El sitio activo de la enzima facilita el acceso del sustrato al oxígeno peroxo reactivo.
- Los residuos de aminoácidos como Lys353 pueden desempeñar un papel en la modulación de la actividad de la VHPO.
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