Clonal adaptive radiation in a constant environment.

Ram Maharjan; Shona Seeto; Lucinda Notley-McRobb; Thomas Ferenci

doi:10.1126/science.1129865

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Clonal adaptive radiation in a constant environment.

Ram Maharjan·Shona Seeto·Lucinda Notley-McRobb·Thomas Ferenci

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Abstract

The evolution of new combinations of bacterial properties contributes to biodiversity and the emergence of new diseases. We investigated the capacity for bacterial divergence with a chemostat culture of Escherichia coli. A clonal population radiated into more than five phenotypic clusters within 26 days, with multiple variations in global regulation, metabolic strategies, surface properties, and nutrient permeability pathways. Most isolates belonged to a single ecotype, and neither periodic selection events nor ecological competition for a single niche prevented an adaptive radiation with a single resource. The multidirectional exploration of fitness space is an underestimated ingredient to bacterial success even in unstructured environments.

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Adaptation, Physiological Biological Evolution Cell Membrane Permeability Culture Media Ecosystem Environment Escherichia coli Gene Expression Regulation, Bacterial Genetic Variation Genotype Glucose Mutation Phenotype Phylogeny Selection, Genetic Surface Properties Journal Article Research Support, Non-U.S. Gov't

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Ram Maharjan, Shona Seeto, Lucinda Notley-McRobb, Thomas Ferenci. 2006-07-06. Clonal adaptive radiation in a constant environment.. https://doi.org/10.1126/science.1129865

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