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Las halogenasas diseñadas dependientes de la flavina catalizan la formación de enlaces C-C a través del

Xuzhong Shen¹, Paras Gupta¹, Pratibha Gandhi¹

¹Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States.

Journal of the American Chemical Society

|January 15, 2026

Resumen

Las halogenasas dependientes de la flavina catalizan los reordenamientos enantioselectivos de semipinacol de los alcoholes alelicos, creando cetonas quirales. Una mutación T52G permitió esta nueva transformación biocatalítica, ampliando el acceso a valiosos andamios moleculares.

Área de la Ciencia:

Química orgánica sintética
Biocatálisis
Ingeniería de enzimas

Sus antecedentes:

El reordenamiento del semipinacol es crucial para sintetizar andamios moleculares.
Las semipinacolasas existentes son limitadas, con solo un ejemplo nuevo en la naturaleza que utiliza la catálisis con ácido de Brønsted.
Las halogenasas dependientes de la flavina (FDH) son conocidas por las reacciones de halogenación.

Objetivo del estudio:

Explorar el potencial de las halogenasas dependientes de la flavina (FDH) para catalizar los reordenamientos del semipinacol.
Desarrollar un método biocatalítico para el reordenamiento enantioselectivo del semipinacol.
Investigar estrategias de ingeniería enzimática para nuevas funciones catalíticas.

Principales métodos:

Se utilizan halogenasas dependientes de la flavina (FDH) para el reordenamiento catalítico del semipinacol.
Se utilizan como sustratos alcoholes alilicos procirales.
Investigó el papel de mutaciones específicas, como T52G, en la actividad enzimática.
Análisis del alcance del sustrato y de la enantioselectividad de la reacción.

Principales resultados:

Las FDHs catalizaron con éxito la reorganización halogenativa enantioselectiva de los alcoholes alílicos.
La plataforma biocatalítica demostró un amplio alcance de sustrato, produciendo cetonas quirales con estereocentros cuaternarios.
Se logró una alta enantioselectividad y un valor k_cat de 16,86 ± 0,97 min^-1, el más alto para la catálisis FDH.
Identificó la mutación T52G como crítica para permitir esta transformación no nativa mediante la remodelación del sitio activo de la enzima.

Conclusiones:

Las halogenasas dependientes de la flavina pueden ser diseñadas para realizar reordenamientos de semipinacol, una función no nativa.
Este estudio presenta el primer ejemplo de construcción asimétrica de enlaces C-C utilizando un FDH.
La plataforma biocatalítica desarrollada proporciona acceso a carbociclos y heterociclos enantioenriquecidos, lo que pone de relieve la flexibilidad catalítica de las enzimas.

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