uu.seUppsala University Publications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Ciprofloxacin selects for RNA polymerase mutations with pleiotropic antibiotic resistance effects
Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology.
Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology.
Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology.
Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology.
Show others and affiliations
2017 (English)In: Journal of Antimicrobial Chemotherapy, ISSN 0305-7453, E-ISSN 1460-2091, Vol. 72, no 1, 75-84 p.Article in journal (Refereed) Published
Abstract [en]

Objectives: Resistance to the fluoroquinolone drug ciprofloxacin is commonly linked to mutations that alter the drug target or increase drug efflux via the major AcrAB-TolC transporter. Very little is known about other mutations that might also reduce susceptibility to ciprofloxacin. We discovered that an Escherichia coli strain experimentally evolved for resistance to ciprofloxacin had acquired a mutation in rpoB, the gene coding for the beta-subunit of RNA polymerase. The aim of this work was to determine whether this mutation, and other mutations in rpoB, contribute to ciprofloxacin resistance and, if so, by which mechanism. Methods: Independent lineages of E. coli were evolved in the presence of ciprofloxacin and clones from endpoint cultures were screened for mutations in rpoB. Ciprofloxacin-selected rpoB mutations were identified and characterized in terms of effects on susceptibility and mode of action. Results: Mutations in rpoB were selected at a high frequency in 3 out of 10 evolved lineages, in each case arising after the occurrence of mutations affecting topoisomerases and drug efflux. All ciprofloxacin-selected rpoB mutations had a high fitness cost in the absence of drug, but conferred a competitive advantage in the presence of ciprofloxacin. RNA sequencing and quantitative RT-PCR analysis showed that expression of mdtK, encoding a multidrug efflux transporter, was significantly increased by the ciprofloxacin-selected rpoB mutations. The susceptibility phenotype was shown to depend on the presence of an active mdtK and a mutant rpoB allele. Conclusions: These data identify mutations in RNA polymerase as novel contributors to the evolution of resistance to ciprofloxacin and show that the phenotype is mediated by increased MdtK-dependent drug efflux.

Place, publisher, year, edition, pages
OXFORD UNIV PRESS , 2017. Vol. 72, no 1, 75-84 p.
National Category
Infectious Medicine Microbiology in the medical area Medicinal Chemistry
Identifiers
URN: urn:nbn:se:uu:diva-319816DOI: 10.1093/jac/dkw364ISI: 000394038700010PubMedID: 27621175OAI: oai:DiVA.org:uu-319816DiVA: diva2:1087826
Funder
Swedish Research CouncilSwedish Foundation for Strategic Research Knut and Alice Wallenberg Foundation
Available from: 2017-04-10 Created: 2017-04-10 Last updated: 2017-04-10Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textPubMed

Search in DiVA

By author/editor
Pietsch, FranziskaBrandis, GerritZorzet, AnnaHuseby, Douglas L.Hughes, Diarmaid
By organisation
Department of Medical Biochemistry and Microbiology
In the same journal
Journal of Antimicrobial Chemotherapy
Infectious MedicineMicrobiology in the medical areaMedicinal Chemistry

Search outside of DiVA

GoogleGoogle Scholar

Altmetric score

Total: 24 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf