Proteomic approach to reveal the regulatory function of aconitase AcnA in oxidative stress response in the antibiotic producer Streptomyces viridochromogenes Tü494

PLoS One. 2014 Feb 3;9(2):e87905. doi: 10.1371/journal.pone.0087905. eCollection 2014.

Abstract

The aconitase AcnA from the phosphinothricin tripeptide producing strain Streptomyces viridochromogenes Tü494 is a bifunctional protein: under iron-sufficiency conditions AcnA functions as an enzyme of the tricarboxylic acid cycle, whereas under iron depletion it is a regulator of iron metabolism and oxidative stress response. As a member of the family of iron regulatory proteins (IRP), AcnA binds to characteristic iron responsive element (IRE) binding motifs and post-transcriptionally controls the expression of respective target genes. A S. viridochromogenes aconitase mutant (MacnA) has previously been shown to be highly sensitive to oxidative stress. In the present paper, we performed a comparative proteomic approach with the S. viridochromogenes wild-type and the MacnA mutant strain under oxidative stress conditions to identify proteins that are under control of the AcnA-mediated regulation. We identified up to 90 differentially expressed proteins in both strains. In silico analysis of the corresponding gene sequences revealed the presence of IRE motifs on some of the respective target mRNAs. From this proteome study we have in vivo evidences for a direct AcnA-mediated regulation upon oxidative stress.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aconitate Hydratase / genetics
  • Aconitate Hydratase / metabolism*
  • Biomarkers / metabolism*
  • Electrophoresis, Gel, Two-Dimensional
  • Gene Expression Regulation, Bacterial*
  • Mutation / genetics
  • Oxidation-Reduction
  • Oxidative Stress*
  • Proteomics*
  • Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
  • Streptomyces / enzymology*
  • Streptomyces / metabolism
  • Tandem Mass Spectrometry

Substances

  • Biomarkers
  • Aconitate Hydratase

Grants and funding

This research was supported by grants from the Deutsche Forschungsgemeinschaft (SPP1152: Wo 485/7-1,2,3) and the Federal Ministry of Education and Research (GenBioCom #0315585A). EM acknowledges the scholarship Aufenthalt für anwendungsorientierte Biowissenschaftler(innen) und Biotechnolog(inn)en in Shanghai und Jiangsu/China from the ministry of Baden-Württemberg. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.