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Light-driven Enzymatic Decarboxylation
Published on: May 22, 2016
Los efectos de los isótopos cinéticos implican el oxeno de hierro como el único oxidante en la N-dealquilación
Tamara S Dowers1, Dan A Rock, Denise A Rock
1Department of Chemistry, P.O. Box 644630, Washington State University, Pullman, Washington 99164-4630, USA.
Journal of the American Chemical Society
|July 22, 2004
Resumen
Las enzimas del citocromo P450 catalizan la N-dealquilación. Utilizando N-óxidos como donantes de oxígeno, los investigadores encontraron que la oxidación se produce a través de una especie de hierro-oxeno, imitando el sistema enzimático completo.
Área de la Ciencia:
- La bioquímica es la bioquímica.
- Enzimología Enzimología.
- Química orgánica es la química orgánica.
Sus antecedentes:
- Las enzimas del citocromo P450 son cruciales en el metabolismo de diversos compuestos.
- Se propone que varios oxidantes participen en las reacciones mediadas por P450.
- La N-dealquilación es una reacción común y fácil catalizada por P450s.
Objetivo del estudio:
- Para investigar el mecanismo de N-dealquilación por las enzimas P450.
- Para determinar el papel de especies oxigenantes específicas en la catálisis del P450.
- Para comparar las vías de oxidación utilizando donantes de oxígeno sustitutos frente al sistema enzimático completo.
Principales métodos:
- N-óxidos utilizados de N,N-dimetilanilinas etiquetadas con 13C2H2 para-sustituidas como sustratos y donantes de oxígeno.
- Empleó las enzimas P450cam y P4502E1.
- Efectos de isótopos cinéticos medidos para las reacciones de N-dealquilación.
- Se compararon los resultados con el sistema estándar NAD(P) H/NAD(P) -P450 reductasa/O2.
Principales resultados:
- Los sistemas de N-óxido replicaron de cerca los perfiles de efecto de isótopos cinéticos del sistema enzimático completo.
- Los perfiles observados fueron consistentes en diferentes enzimas P450 (P450cam y P4502E1).
- Esta imitación sugiere un mecanismo de oxidación conservado.
Conclusiones:
- La oxidación en las reacciones de N-desalquilación mediadas por enzimas P450 se produce exclusivamente a través de un intermediario de hierro-oxeno.
- Los sustratos de N-óxido sirven como sustitutos efectivos para el estudio de los mecanismos de oxidación de P450.
- Los hallazgos proporcionan una fuerte evidencia de la vía de oxeno de hierro en la catálisis de P450.
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