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Evolution of Antibiotic Resistance without Antibiotic Exposure.

ABSTRACT: Antibiotic use is the main driver in the emergence of antibiotic resistance. Another unexplored possibility is that resistance evolves coincidentally in response to other selective pressures. We show that selection in the absence of antibiotics can coselect for decreased susceptibility to several antibiotics. Thus, genetic adaptation of bacteria to natural environments may drive resistance evolution by generating a pool of resistance mutations that selection could act on to enrich resistant mutants when antibiotic exposure occurs.

SUBMITTER: Knoppel A

PROVIDER: S-EPMC5655081 | biostudies-other | 2017 Nov

REPOSITORIES: biostudies-other

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Evolution of Antibiotic Resistance without Antibiotic Exposure.

Knöppel Anna A Näsvall Joakim J Andersson Dan I DI

Antimicrobial agents and chemotherapy 20171024 11

Antibiotic use is the main driver in the emergence of antibiotic resistance. Another unexplored possibility is that resistance evolves coincidentally in response to other selective pressures. We show that selection in the absence of antibiotics can coselect for decreased susceptibility to several antibiotics. Thus, genetic adaptation of bacteria to natural environments may drive resistance evolution by generating a pool of resistance mutations that selection could act on to enrich resistant muta ...[more]

PMID: 28893783

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