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La evidencia de que la replicación de la transferencia del plásmido F subyace a una aparente mutación adaptativa
1Department of Biology, University of Utah, Salt Lake City 84112, USA.
Science (New York, N.Y.)
|April 21, 1995
Resumen
Las mutaciones adaptativas en Escherichia coli están vinculadas a las funciones de transferencia del factor F. La inhibición de la fertilidad evita la reversión dependiente de RecA, lo que sugiere que se producen mutaciones adaptativas durante la replicación del factor F.
Área de la Ciencia:
- Microbiología Microbiología.
- Genética La genética.
- Biología Molecular Biología Molecular
Sus antecedentes:
- La cepa FC40 de Escherichia coli K12 es un modelo para estudiar la mutabilidad adaptativa.
- Esta cepa posee un alelo lac reversible en un plásmido F, lo que permite el estudio de la lactosa utilizando (Lac +) revertentes.
- Las mutaciones adaptativas son un subconjunto específico de mutaciones espontáneas dependientes de las funciones de RecABC.
Objetivo del estudio:
- Investigar el papel de las funciones de transferencia del factor F en la mutabilidad adaptativa.
- Determinar si la transferencia del factor F es necesaria para la formación de revertentes Lac+ adaptativos.
Principales métodos:
- Utilizando Escherichia coli cepa K12 de la cepa FC40.
- Empleando medios selectivos para observar la acumulación de revertentes Lac+.
- Investigando el efecto de la inhibición de la fertilidad en la reversión adaptativa dependiente de RecA.
Principales resultados:
- Las mutaciones adaptativas dependen de las funciones de RecABC.
- La formación de revertentes adaptativos está vinculada a las funciones de transferencia del factor F.
- La inhibición de la fertilidad anula la reversión adaptativa dependiente de RecA.
Conclusiones:
- Las mutaciones adaptativas parecen surgir durante la replicación desde el origen de transferencia del factor F.
- Los loci genéticos en el cromosoma no replicante exhiben una mutación adaptativa mínima en comparación con los loci asociados al factor F.
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