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Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
Estudios biosintéticos de la formación de aziridina en las azicemicinas
Yasushi Ogasawara1, Hung-wen Liu
1Division of Medicinal Chemistry, College of Pharmacy, and Department of Chemistry and Biochemistry, University of Texas at Austin, Austin, Texas 78712, USA.
Journal of the American Chemical Society
|November 26, 2009
Resumen
Las azicemicinas, antibióticos de anguciclina, cuentan con un anillo de aziridina. Los estudios biosintéticos revelan que el ácido aspártico es el precursor de esta porción única de aziridina en estos importantes compuestos.
Área de la Ciencia:
- Microbiología Microbiología.
- La bioquímica es la bioquímica.
- Biología sintética Biología sintética.
Sus antecedentes:
- Las azicemicinas son antibióticos de tipo anguciclina producidos por Kibdelosporangium sp. MJ126-NF4.4 también se encuentra disponible.
- Estos antibióticos poseen un anillo único de aziridina fusionado con su núcleo policetídeo.
Objetivo del estudio:
- Para dilucidar la vía biosintética del anillo de la aziridina en las azicemicinas.
- Para identificar la molécula precursora de la fracción de aziridina.
Principales métodos:
- Experimentos de alimentación etiquetados con isótopos utilizando [1-(13) C] acetato y aminoácidos etiquetados con deuterio.
- Clonado y secuenciación del grupo de genes de la azicemicina (azic).
- Sobreexpresión y purificación de las enzimas de la adeniltransferasa.
- Pruebas enzimáticas para determinar la especificidad del sustrato.
Principales resultados:
- El esqueleto de la anguciclina es biosintetizado por una policetida sintasa tipo II.
- El ácido aspártico fue identificado como el precursor del anillo de aziridina a través de experimentos de trazador de isótopos.
- El clúster de genes azic contiene genes para la síntesis de policetidas, transferasas de adenilil y oxigenasas.
- Los ensayos enzimáticos confirmaron que una adeniltransferasa reconoce específicamente el ácido aspártico.
Conclusiones:
- Se propone una vía biosintética para la formación de anillos de aziridina en las azicemicinas.
- Se confirma que el ácido aspártico es el precursor de la fracción de aziridina.
- Los hallazgos proporcionan una base para futuros estudios bioquímicos sobre la biosíntesis de la aziridina.
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