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Biosíntesis de la versipelostatina: identificación de una enzima catalizada por la [4+2]-cicloadición requerida para
Takuya Hashimoto1, Junko Hashimoto, Kuniko Teruya
1Biotechnology Research Center, The University of Tokyo , 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
Journal of the American Chemical Society
|January 1, 2015
Resumen
Los investigadores identificaron el grupo de genes biosintéticos de la versipelostatina (VST) en Streptomyces. Se descubrió que una enzima, VstJ, cataliza una reacción clave que forma el esqueleto de espirotetronato esencial para la biosíntesis de VST.
Área de la Ciencia:
- Biosíntesis de Productos Naturales de Productos Naturales
- Biología Molecular Biología Molecular
- Enzimología Enzimología.
Sus antecedentes:
- La versipelostatina (VST) es un complejo policetídeo macrocíclico de 17 miembros.
- El VST presenta un esqueleto de espirotetronato único, lo que plantea un desafío para los estudios de biosíntesis.
- La comprensión de la biosíntesis de VST puede proporcionar información sobre la formación de productos naturales de la policetida.
Objetivo del estudio:
- Para identificar el clúster completo de genes biosintéticos de la versipelostatina (VST) (vst).
- Para dilucidar el mecanismo de la formación de esqueletos de espirotetronato en la biosíntesis de VST.
- Para caracterizar el papel de la enzima VstJ en este proceso.
Principales métodos:
- Expresión heteróloga del grupo de genes vst de 108 kb utilizando un vector de cromosoma artificial bacteriano (BAC).
- Identificación y caracterización de un producto intermedio que contiene tetronato.
- Pruebas enzimáticas para determinar la actividad catalítica de VstJ.
Principales resultados:
- Se identificó con éxito todo el clúster de genes biosintéticos VST de 108 kb (vst) de Streptomyces versipellis 4083-SVS6 a través de la expresión heteróloga.
- Se identificó un nuevo intermedio que contiene tetronato.
- Se demostró que la enzima VstJ catalizaba una reacción estereoselectiva de [4+2]-cicloadición, formando el esqueleto de espirotetronato.
Conclusiones:
- El estudio identificó con éxito el clúster de genes biosintéticos VST y los intermediarios clave.
- VstJ juega un papel crucial en la formación estereoselectiva de la estructura del núcleo espirotetronado de VST.
- Este trabajo proporciona una base para una mayor investigación sobre la biosíntesis y la ingeniería del policetido.
![Solid-phase Synthesis of [4.4] Spirocyclic Oximes](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F58508.jpg&w=3840&q=50)
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