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Updated: Mar 22, 2026
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Purification of a High Molecular Mass Protein in Streptococcus mutans
Published on: September 14, 2019
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Streptococcus mutans CcpA Promotes Biofilm Exopolysaccharide Production and Virulence Gene Expression
Yujie Zhang1,2,3,4, Zhanyi Chen1,2,3,4, Meiling Jing1,2,3,4
1Department of Endodontics, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China.
Molecular Oral Microbiology
|March 21, 2026
Summary
The global regulator CcpA controls Streptococcus mutans' ability to form biofilms and produce extracellular polysaccharides (EPS) by directly binding to gtfB and gtfC gene promoters, impacting dental caries development.
Area of Science:
- Microbiology
- Molecular Biology
- Dental Research
Background:
- Streptococcus mutans is a primary cause of dental caries, forming biofilms via extracellular glucans.
- Glucosyltransferases (GTFs), encoded by gtfB/C/D, are key virulence factors in S. mutans biofilm formation.
Purpose of the Study:
- To investigate the role of the global transcriptional regulator CcpA in regulating EPS synthesis and biofilm formation in S. mutans.
- To elucidate the regulatory mechanism of CcpA on GTF gene expression.
Main Methods:
- Construction and analysis of a ccpA in-frame deletion strain of S. mutans.
- Transcriptome analysis (RNA-Seq) to identify differentially expressed genes.
- Electrophoretic mobility shift assays (EMSAs) to confirm direct CcpA-DNA binding.
Main Results:
- Deletion of ccpA impaired S. mutans growth, reduced EPS synthesis, and diminished biofilm formation.
- Transcriptome analysis showed significant downregulation of gtfB and gtfC in the ccpA deletion strain.
- CcpA directly binds to the promoter regions of gtfB and gtfC, with higher affinity for gtfC.
Conclusions:
- CcpA is a critical regulator of EPS production and biofilm formation in S. mutans.
- CcpA directly controls the expression of key virulence genes gtfB and gtfC.
- CcpA's regulatory role offers potential targets for preventing dental caries.
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