Bacillus pumilus Reveals a Remarkably High Resistance to Hydrogen Peroxide Provoked Oxidative Stress

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. Citation: Handtke S, Schroeter R, Jürgen B, Methling K, Schlüter R, et al. (2014) Bacillus umilus Reveals a Remarkably High Resistance to Hydrogen Peroxide Provoked Oxidative Stress. PLoS ONE 9(1): e85625. doi:10.1371/journal.pone.0085625 Editor: Adam Driks, Loyola University Medical Center, United States of America Received September 6, 2013; Accepted December 5, 2013; Published January 20, 2014 Copyright: 2014 Handtke et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. 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. Competing Interests: The transcriptome analysis for this study was financially supported by Henkel KGaA. Dr. Sacha A.F.T. van Hijum is affiliated to NIZO Food Research B.V., and Dr. Karl-Heinz Maurer to AB Enzymes GmbH. Dr. Karl-Heinz Maurer was formerly employed at the company Henkel AG & Co. KGaA (Düsseldorf, Germany) which was involved as an associated partner in one of the projects. There are no patents, products in development or marketed products to declare. This does not alter the authors’ adherence to all the PLOS ONE policies on sharing data and materials, as detailed online in the guide for authors. * E-mail: [email protected] . These authors contributed equally to this work.