Bacitracin sensing in Bacillus subtilis

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • Eva Rietkötter - , University of Göttingen (Author)
  • Diana Hoyer - , Karlsruhe Institute of Technology, University of Göttingen (Author)
  • Thorsten Mascher - , Chair of General Microbiology, Institute of Applied Life Science, Karlsruhe Institute of Technology, University of Göttingen (Author)

Abstract

The extracellular presence of antibiotics is a common threat in microbial life. Their sensitive detection and subsequent induction of appropriate resistance mechanisms is therefore a prerequisite for survival. The bacitracin stress response network of Bacillus subtilis consists of four signal-transducing systems, the two-component systems (TCS) BceRS, YvcPQ and LiaRS, and the extracytoplasmic function (ECF) σ factor σM. Here, we investigated the mechanism of bacitracin perception and the response hierarchy within this network. The BceRS-BceAB TCS/ABC transporter module is the most sensitive and efficient bacitracin resistance determinant. The ABC transporter BceAB not only acts as a bacitracin detoxification pump, but is also crucial for bacitracin sensing, indicative of a novel mechanism of stimulus perception, conserved in Firmicutes bacteria. The Bce system seems to respond to bacitracin directly (drug sensing), whereas the LiaRS TCS and σM respond only at higher concentrations and indirectly to bacitracin action (damage sensing). The YvcPQ-YvcRS system is subject to cross-activation via the paralogous Bce system, and is therefore only indirectly induced by bacitracin. The bacitracin stress response network is optimized to respond to antibiotic gradients in a way that maximizes the gain and minimizes the costs of this stress response.

Details

Original languageEnglish
Pages (from-to)768-785
Number of pages18
JournalMolecular microbiology
Volume68
Issue number3
Publication statusPublished - May 2008
Peer-reviewedYes

External IDs

PubMed 18394148

Keywords