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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
Meroclorinas A-D, antibióticos cíclicos meroterpenoides biosintetizados en vías divergentes con las cloroperoxidasas
Leonard Kaysser1, Peter Bernhardt, Sang-Jip Nam
1Scripps Institution of Oceanography, University of California, San Diego, California 92093, USA.
Journal of the American Chemical Society
|July 13, 2012
Resumen
Las bacterias marinas produjeron cuatro nuevos antibióticos meroterpenoides, meroclorinas A-D, con nuevas estructuras. Se identificó un gen haloperoxidasa dependiente del vanadio (mcl40) como clave para su biosíntesis única.
Área de la Ciencia:
- Química de los productos naturales.
- Microbiología marina microbiología marina.
- La bioquímica es la bioquímica.
Sus antecedentes:
- Los meroterpenoides son productos naturales con diversas actividades biológicas.
- Los microorganismos marinos son una fuente de nuevos compuestos bioactivos.
- Las especies de Streptomyces son conocidas como productoras de antibióticos.
Objetivo del estudio:
- Descubrir y caracterizar nuevos antibióticos meroterpenoides a partir de una bacteria marina.
- Para dilucidar la vía biosintética de estos nuevos compuestos.
- Para identificar las enzimas responsables de las etapas clave de la biosíntesis.
Principales métodos:
- Aislamiento y aclaración de la estructura de nuevos meroterpenoides.
- Proyecto de secuenciación del genoma de la bacteria productora.
- Mutagenesis y expresión heteróloga del grupo de genes biosintéticos.
- Pruebas bioquímicas para determinar la función de las enzimas.
Principales resultados:
- Se identificaron cuatro nuevos meroterpenoides, meroclorinas A-D, con esqueletos químicos sin precedentes.
- Se identificó un grupo de genes de 57.6 kb responsable de la biosíntesis de meroclorina.
- Se encontraron dos genes de la haloperoxidasa dependiente de vanadio (VHPO) dentro del grupo.
- La expresión heteróloga reveló que Mcl40 cataliza una nueva macrociclización inducida por el cloro.
Conclusiones:
- Las meroclorinas A-D representan una nueva clase de antibióticos meroterpenoides.
- El grupo de genes biosintéticos de meroclorina proporciona información sobre la biosíntesis de productos naturales.
- El VHPO Mcl40 cataliza una reacción de macrociclado única, expandiendo el repertorio conocido de transformaciones enzimáticas en la síntesis de productos naturales.
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