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Preparation of Contiguous Bisaziridines for Regioselective Ring-Opening Reactions
Published on: July 28, 2022
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Bases moleculares para la formación enzimática de la aziridina a través de la eliminación del sulfato
Sumire Kurosawa1, Fumihito Hasebe1, Hironori Okamura1
1Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1, Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
Journal of the American Chemical Society
|August 23, 2022
Resumen
Los investigadores aclararon la biosíntesis del anillo de aziridina en los productos naturales. Se descubrió un nuevo mecanismo enzimático que implica la eliminación de sulfato, proporcionando las primeras ideas moleculares sobre la formación de anillos de aziridina.
Área de la Ciencia:
- La bioquímica
- Química orgánica
- Biología molecular
Sus antecedentes:
- Los productos naturales como la mitomicina C y la azinomicina B poseen propiedades antitumorales debido a la alquilación del ADN a través de sus anillos de aziridina.
- Las vías de biosíntesis para la formación de anillos de aziridina en estos compuestos siguen siendo en gran medida desconocidas.
Objetivo del estudio:
- Para investigar la biosíntesis del anillo de aziridina en la vazabitida A, un compuesto estructuralmente relacionado con la azinomicina B.
- Para aclarar el mecanismo enzimático y la base molecular de la formación de anillos de aziridina.
Principales métodos:
- Investigó la biosíntesis de la vazabitida A, identificando Vzb10/11 como la enzima responsable de la formación de anillos de aziridina a través de la eliminación del sulfato.
- Intento de cristalización de Vzb10/11 y de la enzima homóloga AziU3/U2 de la biosíntesis de la azinomicina B.
- Se determinó la estructura cristalina de AziU3 / U2, revelando un nuevo pliegue de proteínas.
Principales resultados:
- Identificó Vzb10/11 como una nueva enzima que cataliza la formación de anillos de aziridina a través de la eliminación de sulfato.
- La estructura cristalina de AziU3 / U2 reveló un pliegue proteico único.
- El análisis estructural mostró que las enzimas optimizan la conformación del sustrato y mejoran la nucleofilicidad del grupo amino para una reacción similar a SN2, formando el anillo de aziridina.
Conclusiones:
- Este estudio proporciona la primera comprensión molecular de la formación de anillos de aziridina en la biosíntesis de productos naturales.
- El mecanismo enzimático identificado ofrece información sobre la síntesis de moléculas biológicamente activas que contienen fracciones de aziridina.
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