Reducción de azida catalizada por mioglobina a través de un intermediario de amida metálica aniónica
Matthias Tinzl1, Johannes V Diedrich2, Peer R E Mittl3
1Laboratory of Organic Chemistry, ETH Zürich, 8093 Zürich, Switzerland.
Journal of the American Chemical Society
|January 24, 2024
Resumen
Las proteínas hemo catalizan la transferencia de nitreno para la formación de enlaces C-N. Este estudio revela cómo la mioglobina reduce las azidas, detallando el intermediario de amida ferosa y su protonación limitadora de velocidad, guiando la ingeniería enzimática para mejores transferasas de nitreno.
Área de la Ciencia:
- Biocatálisis
- Química bioorgánica
- Mecanismos de las enzimas
Sus antecedentes:
- Las proteínas hemo catalizan la transferencia de nitreno para la formación de enlaces estereoselectivos carbono-nitrógeno.
- La transferencia de nitreno biocatalítico está limitada por la reducción competitiva de los precursores de nitreno.
Objetivo del estudio:
- Investigar la reducción de azida por la mioglobina para comprender los factores que controlan los intermediarios de la reacción.
- Obtener conocimientos mecanicistas sobre la reducción de azida catalizada por la proteína hemo.
Principales métodos:
- Espectroscopias UV/vis y de Mössbauer
- Cálculos de la mecánica cuántica
- Cristalografía de rayos X
Principales resultados:
- Se caracteriza por un intermediario de amida ferrosa formado por reducción y protonación de nitreno.
- Identificación de la protonación que limita la velocidad de la amida ferrosa para formar el producto de la amina.
- Se ha demostrado una cascada quimioenzimática para la síntesis de pirroles sustituidos.
Conclusiones:
- Comprensión mecánica de la reducción azida catalizada por la proteína hemo.
- Proporciona una guía para diseñar enzimas de transferasa de nitreno más eficientes.
- La cascada quimioenzimática ofrece una ruta práctica para los pirroles sustituidos.
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