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A Fluorescence-based Method to Study Bacterial Gene Regulation in Infected Tissues
Published on: February 19, 2019
Distinct time-resolved roles for two catabolite-sensing pathways during Streptococcus pyogenes infection
Colin C Kietzman1, Michael G Caparon
1Department of Molecular Microbiology, Washington University School of Medicine, 660 S. Euclid Ave., Box 8230, Saint Louis, MO 63110-1093, USA.
Infection and Immunity
|November 25, 2010
Summary
Glucose significantly impacts Streptococcus pyogenes gene expression via carbon catabolite regulation pathways. The CcpA and LacD.1 regulators control distinct temporal gene expression patterns during infection.
Area of Science:
- Microbiology
- Molecular Biology
- Genomics
Background:
- Gram-positive pathogens utilize carbon catabolite regulation for virulence gene expression.
- Integration of these pathways for temporal and spatial control of the transcriptome is poorly understood.
Purpose of the Study:
- To investigate glucose-mediated gene expression changes in Streptococcus pyogenes.
- To determine the roles of CcpA and LacD.1 pathways in regulating this response in vitro and in vivo.
Main Methods:
- Global transcriptome profiling (RNA-Seq) to analyze gene expression changes.
- In vitro studies using glucose as a carbon source.
- Murine soft tissue infection model to assess in vivo regulation.
Main Results:
- Glucose regulated up to 15% of the S. pyogenes transcriptome.
- CcpA and LacD.1 contributed to 60% of this glucose-regulated subset, exhibiting independent, coregulated, and antagonistic effects.
- Mutants lacking CcpA or LacD.1 showed distinct temporal misregulation patterns in vivo.
Conclusions:
- Carbohydrate availability is crucial for regulating the S. pyogenes transcriptome during infection.
- CcpA and LacD.1 pathways are organized to function differentially over the course of infection, influencing virulence gene expression.
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