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A Fast and Reliable Pipeline for Bacterial Transcriptome Analysis Case study: Serine-dependent Gene Regulation in Streptococcus pneumoniae
Published on: April 25, 2015
Comparative functional analysis of the lac operons in Streptococcus pyogenes
Jennifer A Loughman1, Michael G Caparon
1Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, MO 63110-1093, USA. Loughman_J@kids.wustl.edu
Molecular Microbiology
|March 21, 2007
Summary
Streptococcus pyogenes utilizes a specialized aldolase (LacD.1) for virulence gene regulation, distinct from its paralog (LacD.2) which handles carbohydrate metabolism. This functional divergence highlights an underappreciated bacterial regulatory strategy.
Area of Science:
- Microbiology
- Bacterial genetics
- Molecular biology
Background:
- Streptococcus pyogenes relies on host substrates due to lacking environmental reservoirs.
- Aldolase enzymes like LacD.1 and LacD.2 are involved in carbohydrate utilization pathways.
Purpose of the Study:
- To investigate the regulatory mechanism of the LacD.1 pathway.
- To understand the role of genome context in the evolution of LacD.1's regulatory functions.
- To compare the function and regulation of Lac.1 and Lac.2 loci.
Main Methods:
- Comparative analysis of Lac.1 and Lac.2 loci function and regulation.
- Investigating LacD.1's role in virulence gene regulation.
- Assessing LacD.2's contribution to growth on galactose.
Main Results:
- The Lac.1 operon is constitutively expressed and its regulation by LacD.1 is independent of the tagatose 6-phosphate pathway.
- LacD.1's regulatory function is enhanced by upstream gene truncation.
- Lac.2 expression is environmentally responsive, and LacD.2 facilitates growth on galactose.
Conclusions:
- The Lac.1 locus is specialized for gene regulation, while the Lac.2 locus is optimized for carbohydrate utilization.
- Adaptation of aldolase enzymes for transcriptional regulation is a potentially widespread prokaryotic strategy.
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