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El espiroplasma nada por un cambio procesal en la helicidad del cuerpo
Joshua W Shaevitz1, Joanna Y Lee, Daniel A Fletcher
1Department of Integrative Biology, University of California, Berkeley, 459 Evans Hall, Berkeley, California 94720, USA. jshaevitz@berkeley.edu
Cell
|September 24, 2005
Resumen
Pequeñas bacterias helicoidales, Spiroplasma, nadan usando un nuevo mecanismo. En lugar de la rotación flagelar, generan propulsión a través de pares de torceduras que se propagan a lo largo de sus cuerpos, lo que permite el movimiento direccional.
Área de la Ciencia:
- Microbiología Microbiología.
- La biofísica es la biofísica.
- La motilidad bacteriana.
Sus antecedentes:
- Los organismos microscópicos requieren estrategias únicas para la locomoción en ambientes líquidos.
- La natación procariota se logra típicamente a través de la rotación flagelar.
- Los espiroplasmas son bacterias helicoidales conocidas por infectar plantas e insectos.
Objetivo del estudio:
- Para investigar el mecanismo de natación del espiroplasma.
- Para aclarar los principios biofísicos que subyacen a la motilidad de Spiroplasma.
- Para identificar estrategias alternativas de locomoción bacteriana más allá de la rotación flagelar.
Principales métodos:
- Análisis cuantitativo de la cinemática celular durante la natación libre.
- Microscopía de alta resolución para observar el movimiento bacteriano.
- Modelado biofísico de la propagación de ondas y deformación celular.
Principales resultados:
- La propulsión de espiroplasma es generada por la propagación de pares de kink a lo largo del cuerpo celular.
- Un cambio dinámico en la helicidad celular crea ondas propulsivas.
- Este mecanismo permite el movimiento dirigido en líquido.
Conclusiones:
- Los espiroplasmas emplean un mecanismo de natación único y no flagellar.
- La propagación de pares de pares y los cambios dinámicos de helicidad son clave para su motilidad.
- Este descubrimiento amplía nuestra comprensión de las estrategias de locomoción bacteriana.
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