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Mutation accumulation and horizontal gene transfer in Escherichia coli colonizing the gut of old mice.

ABSTRACT: The ecology and environment of the microbes that inhabit the mammalian intestine undergoes several changes as the host ages. Here, we ask if the selection pressure experienced by a new strain colonizing the aging gut differs from that in the gut of young adults. Using experimental evolution in mice after a short antibiotic treatment, as a model for a common clinical situation, we show that a new colonizing E. coli strain rapidly adapts to the aging gut via both mutation accumulation and bacteriophage-mediated horizontal gene transfer (HGT). The pattern of evolution of E. coli in aging mice is characterized by a larger number of transposable element insertions and intergenic mutations compared to that in young mice, which is consistent with the gut of aging hosts harboring a stressful and iron limiting environment.

SUBMITTER: Barreto HC

PROVIDER: S-EPMC7518454 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Mutation accumulation and horizontal gene transfer in Escherichia coli colonizing the gut of old mice.

Barreto Hugo C HC Frazão Nelson N Sousa Ana A Konrad Anke A Gordo Isabel I

Communicative & integrative biology 20200624 1

The ecology and environment of the microbes that inhabit the mammalian intestine undergoes several changes as the host ages. Here, we ask if the selection pressure experienced by a new strain colonizing the aging gut differs from that in the gut of young adults. Using experimental evolution in mice after a short antibiotic treatment, as a model for a common clinical situation, we show that a new colonizing E. coli strain rapidly adapts to the aging gut via both mutation accumulation and b ...[more]

PMID: 33014261

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