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A multifaceted small RNA modulates gene expression upon glucose limitation in Staphylococcus aureus.

ABSTRACT: Pathogenic bacteria must rapidly adapt to ever-changing environmental signals resulting in metabolism remodeling. The carbon catabolite repression, mediated by the catabolite control protein A (CcpA), is used to express genes involved in utilization and metabolism of the preferred carbon source. Here, we have identified RsaI as a CcpA-repressed small non-coding RNA that is inhibited by high glucose concentrations. When glucose is consumed, RsaI represses translation initiation of mRNAs encoding a permease of glucose uptake and the FN3K enzyme that protects proteins against damage caused by high glucose concentrations. RsaI also binds to the 3' untranslated region of icaR mRNA encoding the transcriptional repressor of exopolysaccharide production and to sRNAs induced by the uptake of glucose-6 phosphate or nitric oxide. Furthermore, RsaI expression is accompanied by a decreased transcription of genes involved in carbon catabolism pathway and an activation of genes involved in energy production, fermentation, and nitric oxide detoxification. This multifaceted RNA can be considered as a metabolic signature when glucose becomes scarce and growth is arrested.

SUBMITTER: Bronesky D

PROVIDER: S-EPMC6418428 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature

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A multifaceted small RNA modulates gene expression upon glucose limitation in <i>Staphylococcus aureus</i>.

Bronesky Delphine D Desgranges Emma E Corvaglia Anna A François Patrice P Caballero Carlos J CJ Prado Laura L Toledo-Arana Alejandro A Lasa Inigo I Moreau Karen K Vandenesch François F Marzi Stefano S Romby Pascale P Caldelari Isabelle I

The EMBO journal 20190213 6

Pathogenic bacteria must rapidly adapt to ever-changing environmental signals resulting in metabolism remodeling. The carbon catabolite repression, mediated by the catabolite control protein A (CcpA), is used to express genes involved in utilization and metabolism of the preferred carbon source. Here, we have identified RsaI as a CcpA-repressed small non-coding RNA that is inhibited by high glucose concentrations. When glucose is consumed, RsaI represses translation initiation of mRNAs encoding ...[more]

PMID: 30760492

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Dataset Information

A multifaceted small RNA modulates gene expression upon glucose limitation in Staphylococcus aureus.

Publications

A multifaceted small RNA modulates gene expression upon glucose limitation in <i>Staphylococcus aureus</i>.

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