Metabolome and transcriptome-wide effects of the carbon storage regulator A in enteropathogenic Escherichia coli.

ABSTRACT: The carbon storage regulator A (CsrA) is a conserved swivel of a global regulatory system known to regulate central carbon pathways, biofilm formation, motility, and pathogenicity. The aim of this study was to characterize changes in major metabolic pathways induced by CsrA in the human enteropathogenic Escherichia coli (EPEC) strain E2348/69. The EPEC strain E2348/69 and a csrA deletion mutant were grown under virulence factor inducing conditions and characterized by a combined analysis of their metabolomes and transcriptomes. Of the 159 metabolites identified from untargeted GC/MS and LC/MS data, 70 were significantly (fold change ≥ 1.5; p-value ≤ 0.05) regulated between the knockout and the wildtype strain. A lack of csrA led to an upregulation of upper glycolysis and glycogen synthesis pathways, whereas lower glycolysis and the citric acid cycle were downregulated. Associated pathways from the citric acid cycle like aromatic amino acid and siderophore biosynthesis were also negatively influenced. The nucleoside salvage pathways were featured by an accumulation of nucleosides and nucleobases, and a downregulation of nucleotides. In addition, a pronounced downregulation of lyso-lipid metabolites was observed. A drastic change in the morphology in the form of vesicle-like structures of the csrA knockout strain was visible by electron microscopy, which is supposed to be a consequence of a strong upregulation of colanic acid synthesis. The findings expand the scope of pathways affected by the csrA regulon and emphasize its importance as a global regulator.

ORGANISM(S): Escherichia coli

PROVIDER: GSE103415 | GEO | 2018/12/15

REPOSITORIES: GEO