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Conservación inesperada y transmisión global de los plásmidos de virulencia agrobacteriana
Alexandra J Weisberg1, Edward W Davis1,2, Javier Tabima1
1Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR 97331, USA.
Science (New York, N.Y.)
|June 6, 2020
Resumen
Las bacterias patógenas como Agrobacteria usan plásmidos de virulencia para infectar las plantas. Sorprendentemente, estos plásmidos oncogénicos se originan en pocos linajes, con la transmisión impulsando su propagación y diversificación global.
Área de la Ciencia:
- Microbiología
- Biología evolutiva
- Patología vegetal
Sus antecedentes:
- La evolución y propagación de los patógenos representan una amenaza significativa para las especies huésped.
- Las agrobacterias utilizan plásmidos oncogénicos Ti o Ri para la transferencia de genes de las plantas y la inducción de enfermedades.
Objetivo del estudio:
- Desarrollar una estrategia para la caracterización de las plasmidas de virulencia.
- Analizar la historia evolutiva y los patrones epidemiológicos de los plásmidos oncogénicos en Agrobacteria.
Principales métodos:
- Desarrolló una nueva estrategia para la caracterización del plásmido de virulencia.
- Analizó cientos de cepas de Agrobacteria recogidas a nivel mundial (1927-2017) de diversas especies huésped.
- Inferir la historia evolutiva mediante la caracterización de las características que influyen en la plasticidad del plásmido.
Principales resultados:
- Contrariamente a las expectativas de alta recombinación, los plásmidos oncogénicos se derivan de unos pocos linajes conservados.
- Las características clave identificadas que promueven o restringen la plasticidad evolutiva del plásmido.
- Se han descubierto patrones epidemiológicos que demuestran el papel crucial de la transmisión de plásmidos en la diversificación y propagación de patógenos.
Conclusiones:
- La transmisión de plásmidos es un impulsor clave de la diversificación, persistencia y diseminación global de las Agrobacteria.
- La trayectoria evolutiva de los plásmidos oncogénicos está formada por un número limitado de linajes conservados.
- Comprender la evolución de los plásmidos es fundamental para controlar las enfermedades de las plantas causadas por Agrobacteria.
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