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Activación de quórum a distancia: patrones espaciotemporales de regulación génica a partir de la difusión de una
Gabriel E Dilanji1, Jessica B Langebrake, Patrick De Leenheer
1Department of Physics, University of Florida, Gainesville, Florida 32611-8440, United States.
Journal of the American Chemical Society
|March 1, 2012
Resumen
La detección de quórum bacteriana (QS) utiliza autoinductores difusores para sincronizar la expresión génica. Este estudio revela que QS puede coordinar efectivamente el comportamiento bacteriano a distancias de centímetros a través de la difusión, incluso en entornos heterogéneos.
Área de la Ciencia:
- Microbiología Microbiología.
- Biología de Sistemas Biología de Sistemas.
- La biofísica es la biofísica.
Sus antecedentes:
- La detección de quórum (QS) permite a las bacterias regular la expresión génica colectivamente utilizando moléculas autoinducidoras.
- QS se estudia típicamente en cultivos bien agitados, pero las bacterias a menudo existen en entornos heterogéneos donde la difusión domina el transporte de señales.
Objetivo del estudio:
- Investigar el alcance efectivo y las capacidades de sincronización de QS en distancias mediadas por difusión.
- Para explorar los patrones espaciotemporales de la expresión génica en respuesta a la difusión de autoinductores.
Principales métodos:
- Las mediciones experimentales combinadas con el modelado matemático.
- Incorporó bacterias QS en un carril de agar e introdujo un autoinducidor exógeno en un extremo.
- Se midió la expresión génica del reportero QS en el espacio y el tiempo a medida que la señal se difundía.
Principales resultados:
- Los autoinductores difusores activaron los genes reporteros con eficacia en distancias de ~ 1 cm en ~ 10 horas.
- Se observaron patrones únicos de excitación espacio-temporal en cepas QS de tipo salvaje.
- Los patrones de activación de QS mostraron una sorprendente insensibilidad a la señal de distancia recorrida.
Conclusiones:
- El transporte difusivo de autoinductores puede sincronizar la expresión génica bacteriana a distancias macroscópicas.
- Los modelos matemáticos que incorporan difusión, crecimiento bacteriano y activación cooperativa reproducen con precisión las observaciones experimentales.
- QS es eficaz en la coordinación del comportamiento bacteriano incluso en entornos espaciales complejos y limitados por la difusión.
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