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Genetic Manipulation in Δku80 Strains for Functional Genomic Analysis of Toxoplasma gondii
Published on: July 12, 2013
El fago satélite TLCφ permite la conversión toxigénica por el fago CTX a través de la alteración del sitio dif
Faizule Hassan1, M Kamruzzaman, John J Mekalanos
1Molecular Genetics Laboratory, International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka-1212, Bangladesh.
Nature
|October 15, 2010
Resumen
Un nuevo fago satélite, TLC-Knφ1, se integra en los cromosomas de Vibrio cholerae, restaurando la forma celular y facilitando la integración de la propagación de la toxina del cólera (CTXφ). Esto revela la cooperación de los fagos en la evolución del patógeno.
Área de la Ciencia:
- Microbiología Microbiología.
- Bacteriología Bacteriología.
- Virología Virología.
Sus antecedentes:
- Los cromosomas bacterianos albergan elementos genéticos integrados de función desconocida.
- El profago CTXφ, que codifica la toxina del cólera en Vibrio cholerae, está cerca del elemento críptico (TLC) vinculado a la toxina de función desconocida.
Objetivo del estudio:
- Caracterice el elemento TLC y su papel en Vibrio cholerae.
- Investigar la interacción entre el TLC, los fagos filamentosos y la estructura del cromosoma bacteriano.
Principales métodos:
- Secuenciación del genoma y caracterización del elemento relacionado con el TLC.
- Análisis de la secuencia de recombinación dif y su papel en la resolución mediada por XerC/XerD.
- Análisis fenotípico de cepas de Vibrio cholerae con y sin integración TLC-Knφ1, centrado en la morfología celular y la lisogenia CTXφ.
Principales resultados:
- El elemento TLC es un fago filamentoso satélite (TLC-Knφ1) que utiliza los genes de otro fago (fs2φ) para la morfogénesis.
- El genoma TLC-Knφ1 contiene una secuencia dif-like, crucial para la resolución de los dímeros cromosómicos.
- La integración de TLC-Knφ1 restauró la morfología celular normal en mutantes de V. cholerae con sitios dif defectuosos.
- La lisogenia de TLC-Knφ1 facilitó la integración de CTXφ en el sitio dif restaurado, lo que permitió la conversión toxigénica.
Conclusiones:
- TLC-Knφ1 es un fago satélite que restaura funcionalmente el sitio dif en Vibrio cholerae.
- Las interacciones cooperativas entre múltiples fagos son críticas para la aparición del patógeno Vibrio cholerae.
- Este estudio aclara un nuevo mecanismo de interacción entre fagos y bacterias que influye en la evolución de los patógenos.
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