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La descarboxilación no oxidativa de los derivados de la glicina por una peroxidasa
Rheem A Totah1, Robert P Hanzlik
1Department of Medicinal Chemistry, University of Kansas, Lawrence 66045-7582, USA.
Journal of the American Chemical Society
|August 22, 2002
Resumen
La peroxidasa del rábano picante (HRP) cataliza rápidamente la descarboxilación no oxidativa de los derivados de N-alquilo-N-fenilglicina. Esta nueva reacción, inhibida por el peróxido, produce N-alquilo-N-metilanilinas con un rendimiento del 100%.
Área de la Ciencia:
- La bioquímica es la bioquímica.
- Enzimología Enzimología.
Sus antecedentes:
- La peroxidasa del rábano picante (HRP) es una enzima bien estudiada.
- Las reacciones estándar de HRP involucran procesos oxidativos catalizados por el peróxido.
Objetivo del estudio:
- Para investigar la actividad catalítica no oxidativa de HRP.
- Para dilucidar el mecanismo de la descarboxilación no oxidativa catalizada por HRP.
Principales métodos:
- Reacciones enzimáticas en condiciones anaerobias y libres de peróxido.
- Substrato: Derivados del N-alquilo-N-fenilglicina. también conocido como N-alquilo-N-fenilglicina.
- Análisis del producto utilizando el tampón D2O para rastrear la incorporación de deuterio.
Principales resultados:
- El HRP catalizó una descarboxilación rápida y no oxidativa de sustratos.
- Se observó un rendimiento del 100% de las N-alquilo-N-metilanilinas.
- Incorporación de deuterio en el grupo metilo del producto cuando se utilizó el tampón D2O.
- Reacción inhibida por el peróxido y el oxígeno, lo que indica un mecanismo no estándar.
Conclusiones:
- Se propone un nuevo mecanismo cíclico para la descarboxilación no oxidativa catalizada por HRP.
- El mecanismo implica la abstracción de electrones por el HRP férrico, la descarboxilación del sustrato y la reducción por el HRP ferroso.
- Este hallazgo amplía el conocido repertorio catalítico de HRP.
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