Bacillus pumilus reveals a remarkably high resistance to hydrogen peroxide provoked oxidative stress

PLoS One. 2014 Jan 20;9(1):e85625. doi: 10.1371/journal.pone.0085625. eCollection 2014.

Abstract

Bacillus pumilus is characterized by a higher oxidative stress resistance than other comparable industrially relevant Bacilli such as B. subtilis or B. licheniformis. In this study the response of B. pumilus to oxidative stress was investigated during a treatment with high concentrations of hydrogen peroxide at the proteome, transcriptome and metabolome level. Genes/proteins belonging to regulons, which are known to have important functions in the oxidative stress response of other organisms, were found to be upregulated, such as the Fur, Spx, SOS or CtsR regulon. Strikingly, parts of the fundamental PerR regulon responding to peroxide stress in B. subtilis are not encoded in the B. pumilus genome. Thus, B. pumilus misses the catalase KatA, the DNA-protection protein MrgA or the alkyl hydroperoxide reductase AhpCF. Data of this study suggests that the catalase KatX2 takes over the function of the missing KatA in the oxidative stress response of B. pumilus. The genome-wide expression analysis revealed an induction of bacillithiol (Cys-GlcN-malate, BSH) relevant genes. An analysis of the intracellular metabolites detected high intracellular levels of this protective metabolite, which indicates the importance of bacillithiol in the peroxide stress resistance of B. pumilus.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacillus / drug effects*
  • Bacillus / genetics
  • Bacillus / metabolism
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism
  • Gene Expression Regulation, Bacterial / drug effects*
  • Hydrogen Peroxide / pharmacology*
  • Oxidative Stress / drug effects*
  • Oxidative Stress / physiology
  • Regulon / drug effects*
  • Regulon / physiology
  • Repressor Proteins / genetics
  • Repressor Proteins / metabolism

Substances

  • Bacterial Proteins
  • Repressor Proteins
  • Hydrogen Peroxide

Grants and funding

This work was financially supported by funds of the Competence Network “Mipro - Microbes for production: A genomics-based approach to engineer novel industrial production strains” (0315594B) by the German Federal Ministry of Education and Research (BMBF, www.bmbf.de) and the project “Ausbau und Profilierung von COAST Fun-Gene” (UG11043, ESF/IV-BM-B35-0003/12) of the Bildungsministerium of Mecklenburg-Vorpommern (www.regierung-mv.de). The transcriptome analysis was financially supported by the Henkel KGaA (www.henkel.de). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.