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A Straightforward Method for Glucosinolate Extraction and Analysis with High-pressure Liquid Chromatography HPLC
Published on: March 15, 2017
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Una vía metabólica para la activación de los glucosinolatos dietéticos por un simbionte intestinal humano
Catherine S Liou1, Shannon J Sirk1, Camil A C Diaz1
1Department of Chemical Engineering, Stanford University, Stanford, CA 94305, USA.
Cell
|February 22, 2020
Resumen
Las bacterias intestinales como Bacteroides thetaiotaomicron metabolizan los glucosinolatos de las verduras Brassica en isotiocianatos que previenen el cáncer. Este estudio identifica los genes específicos responsables de este proceso metabólico crucial.
Área de la Ciencia:
- Microbiología
- La bioquímica
- Ciencias de la nutrición
Sus antecedentes:
- Los glucosinolatos, que se encuentran en los vegetales Brassica, están relacionados con un riesgo reducido de cáncer.
- La microbiota intestinal juega un papel en el metabolismo de los glucosinolatos en compuestos beneficiosos.
- Los isotiocianatos son metabolitos quimiopreventivos derivados de los glucosinolatos.
Objetivo del estudio:
- Identificar los mecanismos genéticos y bioquímicos detrás de la activación del glucosinolato por las bacterias intestinales.
- Comprender el papel de Bacteroides thetaiotaomicron en el procesamiento de los glucosinolatos de la dieta.
Principales métodos:
- Pantalla de inserción de transposones en todo el genoma en Bacteroides thetaiotaomicron.
- Análisis de la expresión génica en Bacteroides fragilis.
- Pruebas enzimáticas in vitro.
- Medición de la producción de isotiocianato gastrointestinal en ratones monocolonizados.
Principales resultados:
- Se identificó un operón (BT2159-BT2156) como esencial para el metabolismo de los glucosinolatos en B. thetaiotaomicron.
- La expresión de estos genes confiere la capacidad de metabolismo de los glucosinolatos a Bacteroides fragilis.
- La formación de isotiocianato in vitro requiere enzimas específicas (BT2158 y BT2156 o BT2157).
- Un mutante específico (BtΔ2157) mostró una reducción de la producción de isotiocianato in vivo.
Conclusiones:
- Bacteroides thetaiotaomicron posee una vía genética definida para el metabolismo del glucosinolato.
- Esta vía permite la producción de isotiocianatos quimiopreventivos a partir de los glucosinolatos de la dieta.
- Los hallazgos aclaran una interacción clave entre el huésped y el microbio en el procesamiento de nutrientes y la prevención del cáncer.
Palabras clave:
Bacteroides thetaiotaomicron y sus derivadosGlucosinolato y sus derivadosMicrobios en el intestinoel isotiocianatoy la mirosinasaFito-nutrienteMás Videos Relacionados
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