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Un análogo de la rebecamicina proporciona una defensa de nicho codificada por plásmido
Ethan B Van Arnam1, Antonio C Ruzzini1, Clarissa S Sit1
1Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School , 240 Longwood Ave., Boston, Massachusetts 02115, United States.
Journal of the American Chemical Society
|November 5, 2015
Resumen
Los investigadores descubrieron la 9-metoxirrecamicina, un nuevo análogo del indolocarbazol, producido por simbiontes bacterianos de hormigas que cultivan hongos. Esta molécula, previamente críptica, puede mediar la competencia entre las cepas bacterianas en este nicho ecológico especializado.
Área de la Ciencia:
- Microbiología
- Biología Química
- Ecología
Sus antecedentes:
- Los simbiontes bacterianos en las hormigas que cultivan hongos se enfrentan a la competencia de otras cepas bacterianas.
- Los indolocarbazoles, como la rebecamicina, son una clase importante de productos naturales con propiedades antitumorales.
- Estudios metagenómicos previos sugirieron la existencia de indolocarbazoles modificados, pero los metabolitos no fueron descubiertos.
Objetivo del estudio:
- Investigar las pequeñas moléculas involucradas en la competencia bacteriana dentro de la simbiosis de hormigas que cultivan hongos.
- Identificar y caracterizar los nuevos productos naturales producidos por estas bacterias especializadas.
- Para aclarar la vía de biosíntesis de un análogo de indolocarbazol recién descubierto.
Principales métodos:
- Cultivo de simbiontes bacterianos de hormigas que cultivan hongos.
- Análisis metabólico para identificar nuevas moléculas pequeñas.
- Análisis genómico y bioinformático para identificar grupos de genes biosintéticos.
- Síntesis química y aclaración estructural del compuesto identificado.
Principales resultados:
- Descubrimiento y caracterización de la 9-metoxirrebecamicina, un análogo de la rebecamicina.
- Identificación del conjunto completo de genes biosintéticos para la 9-metoxirrecamicina.
- El clúster de genes biosintéticos está codificado por plásmidos, similar a otros sistemas de péptidos antimicrobianos.
- La molécula recién descubierta es producida por simbiontes bacterianos de hormigas que cultivan hongos.
Conclusiones:
- La 9-metoxirebecamicina es un nuevo indolocarbazol producido por bacterias asociadas a las hormigas.
- La vía biosintética codificada por el plásmido sugiere un papel en el antagonismo interbacteriano.
- Este descubrimiento arroja luz sobre la ecología química y la dinámica de la competencia en comunidades microbianas especializadas.
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