Bacillus subtilis as a platform for molecular characterisation of regulatory mechanisms of Enterococcus faecalis resistance against cell wall antibiotics

Publikation: Beitrag in FachzeitschriftForschungsartikelBeigetragenBegutachtung

Beitragende

  • Chong Fang - (Autor:in)
  • Emanuel Stiegeler - (Autor:in)
  • Gregory M Cook - , University of Otago (Autor:in)
  • Thorsten Mascher - , Ludwig-Maximilians-Universität München (LMU) (Autor:in)
  • Susanne Gebhard - (Autor:in)

Abstract

To combat antibiotic resistance of Enterococcus faecalis, a better understanding of the molecular mechanisms, particularly of antibiotic detection, signal transduction and gene regulation is needed. Because molecular studies in this bacterium can be challenging, we aimed at exploiting the genetically highly tractable Gram-positive model organism Bacillus subtilis as a heterologous host. Two fundamentally different regulators of E. faecalis resistance against cell wall antibiotics, the bacitracin sensor BcrR and the vancomycin-sensing two-component system VanSB-VanRB, were produced in B. subtilis and their functions were monitored using target promoters fused to reporter genes (lacZ and luxABCDE). The bacitracin resistance system BcrR-BcrAB of E. faecalis was fully functional in B. subtilis, both regarding regulation of bcrAB expression and resistance mediated by the transporter BcrAB. Removal of intrinsic bacitracin resistance of B. subtilis increased the sensitivity of the system. The lacZ and luxABCDE reporters were found to both offer sensitive detection of promoter induction on solid media, which is useful for screening of large mutant libraries. The VanSB-VanRB system displayed a gradual dose-response behaviour to vancomycin, but only when produced at low levels in the cell. Taken together, our data show that B. subtilis is a well-suited host for the molecular characterization of regulatory systems controlling resistance against cell wall active compounds in E. faecalis. Importantly, B. subtilis facilitates the careful adjustment of expression levels and genetic background required for full functionality of the introduced regulators.

Details

OriginalspracheEnglisch
Aufsatznummere93169
FachzeitschriftPloS one
Jahrgang9
Ausgabenummer3
PublikationsstatusVeröffentlicht - 2014
Peer-Review-StatusJa
Extern publiziertJa

Externe IDs

PubMedCentral PMC3968067
Scopus 84899862633

Schlagworte

Schlagwörter

  • Anti-Bacterial Agents/pharmacology, Bacillus subtilis/genetics, Cell Wall/metabolism, Drug Resistance, Bacterial/genetics, Enterococcus faecalis/drug effects, Gene Expression, Genes, Bacterial, Genes, Reporter, Microbial Sensitivity Tests, Promoter Regions, Genetic, Transduction, Genetic

Bibliotheksschlagworte