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Updated: Aug 13, 2026
12:06
Generation of a Gene-disrupted Streptococcus mutans Strain Without Gene Cloning
Published on: October 23, 2017
[Streptococcus mutans glucosyltransferase: isolation and its ability to synthesize polysaccharides]
Summary
Extracellular glucosyltransferases (GTF) from Streptococcus mutans synthesize both water-soluble and insoluble glucans. Enzyme activity varied between serotypes, with serotype c strains showing a greater capacity for water-soluble glucan synthesis.
Area of Science:
- Microbiology
- Enzymology
- Biochemistry
Context:
- Streptococcus mutans is a primary etiological agent of dental caries.
- Extracellular glucosyltransferases (GTF) produced by S. mutans are key virulence factors.
- GTFs synthesize glucans from sucrose, contributing to biofilm formation and adherence.
Purpose:
- To characterize extracellular glucosyltransferases (GTF) from different strains of Streptococcus mutans.
- To compare the glucan synthesis capabilities of GTFs from S. mutans serotype g and serotype c.
- To investigate the complexity and enzymatic activity of S. mutans GTFs.
Summary:
- Extracellular glucosyltransferases (GTF) were successfully extracted from S. mutans strains (serotypes g and c) using ammonium sulfate precipitation with over 50% yield.
- All extracted enzyme preparations demonstrated the ability to synthesize both water-soluble and water-insoluble glucans.
- Polyacrylamide gel electrophoresis revealed the complex, multi-component nature of S. mutans GTFs. Significant differences in polysaccharide synthesis were observed between serotypes: GTFs from serotype g strains produced similar amounts of water-soluble and insoluble glucans, while GTFs from serotype c strains synthesized approximately 10 times more water-soluble glucan than water-insoluble glucan. No fructosyltransferase activity was detected.
Impact:
- Provides insights into the biochemical diversity of GTFs among different S. mutans serotypes.
- Highlights strain-specific differences in glucan synthesis, potentially influencing cariogenic potential.
- Contributes to understanding the enzymatic mechanisms underlying S. mutans virulence and biofilm formation.
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