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Potential for adaptation overrides cost of resistance.

ABSTRACT: AIM:To investigate the cost of antibiotic resistance versus the potential for resistant clones to adapt in maintaining polymorphism for resistance. MATERIALS & METHODS:Experimental evolution of Escherichia coli carrying different resistance alleles was performed under an environment devoid of antibiotics and evolutionary parameters estimated from their frequencies along time. RESULTS & CONCLUSION:Costly resistance mutations were found to coexist with lower cost resistances for hundreds of generations, contrary to the hypothesis that the cost of a resistance dictates its extinction. Estimated evolutionary parameters for the different resistance backgrounds suggest a higher adaptive potential of clones with costly antibiotic resistance mutations, overriding their initial cost of resistance and allowing their maintenance in the absence of drugs.

SUBMITTER: Moura de Sousa J

PROVIDER: S-EPMC4663674 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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Potential for adaptation overrides cost of resistance.

Moura de Sousa Jorge J Sousa Ana A Sousa Ana A Sousa Ana A Bourgard Catarina C Gordo Isabel I

Future microbiology 20150907 9

<h4>Aim</h4>To investigate the cost of antibiotic resistance versus the potential for resistant clones to adapt in maintaining polymorphism for resistance.<h4>Materials & methods</h4>Experimental evolution of Escherichia coli carrying different resistance alleles was performed under an environment devoid of antibiotics and evolutionary parameters estimated from their frequencies along time.<h4>Results & conclusion</h4>Costly resistance mutations were found to coexist with lower cost resistances ...[more]

PMID: 26343510

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