Transcriptome analysis of Rhodobacter capsulatus grown on different nitrogen sources


Erkal N. A. , Eser M. G. , Ozgur E., GÜNDÜZ U. , EROĞLU İ. , Yucel M.

ARCHIVES OF MICROBIOLOGY, vol.201, no.5, pp.661-671, 2019 (Journal Indexed in SCI) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 201 Issue: 5
  • Publication Date: 2019
  • Doi Number: 10.1007/s00203-019-01635-x
  • Title of Journal : ARCHIVES OF MICROBIOLOGY
  • Page Numbers: pp.661-671
  • Keywords: Photoheterotrophic growth, Rhodobacter capsulatus, Purple non-sulfur bacteria, Microarray, Hydrogen metabolism, Acetate metabolism, HYDROGEN-PRODUCTION, PHOTOHETEROTROPHIC GROWTH, RHODOSPIRILLUM-RUBRUM, ACETATE ASSIMILATION, COMPLEX I, METABOLISM, LYASE, PATHWAYS, FIXATION, BACTERIA

Abstract

This study investigated the effect of different nitrogen sources, namely, ammonium chloride and glutamate, on photoheterotrophic metabolism of Rhodobacter capsulatus grown on acetate as the carbon source. Genes that were significantly differentially expressed according to Affymetrix microarray data were categorized into Clusters of Orthologous Groups functional categories and those in acetate assimilation, hydrogen production, and photosynthetic electron transport pathways were analyzed in detail. Genes related to hydrogen production metabolism were significantly downregulated in cultures grown on ammonium chloride when compared to those grown on glutamate. In contrast, photosynthetic electron transport and acetate assimilation pathway genes were upregulated. In detail, aceA encoding isocitrate lyase, a unique enzyme of the glyoxylate cycle and ccrA encoding the rate limiting crotonyl-CoA carboxylase/reductase enzyme of ethylmalonyl-coA pathway were significantly upregulated. Our findings indicate for the first time that R. capsulatus can operate both glyoxylate and ethylmalonyl-coA cycles for acetate assimilation.