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Updated: May 9, 2026
09:51
Purification of a High Molecular Mass Protein in Streptococcus mutans
Published on: September 14, 2019
Lytic bacteriophages ofStreptococcus mutans.
1Department of Microbiology, School of Dentistry, University of Maryland at Baltimore, 21201, Baltimore, Maryland, USA.
Current Microbiology
|July 10, 2013
Summary
Three novel bacteriophages (M102, e10, f1) infecting Streptococcus mutans were characterized. These lytic phages exhibit distinct host ranges but share significant genomic similarities, suggesting a common evolutionary origin.
Area of Science:
- Microbiology
- Virology
- Bacteriology
Background:
- Streptococcus mutans is a primary agent of dental caries.
- Bacteriophages (phages) are viruses that infect bacteria and can be used to target specific bacterial strains.
- Understanding phage-host interactions is crucial for developing novel therapeutic strategies.
Purpose of the Study:
- To isolate and characterize novel bacteriophages targeting Streptococcus mutans.
- To investigate the host range, genomic features, and evolutionary relationships of these phages.
Main Methods:
- Phage isolation and plaque assays on various Streptococcus mutans serotypes.
- Electron microscopy for phage morphology.
- DNA extraction, restriction enzyme digestion, and Southern blot hybridization.
- Analysis of genome size and base composition.
Main Results:
- Three strictly lytic phages (M102, e10, f1) were identified, each with a specific host range (serotypes c, e, f, respectively).
- Phage sensitivity was not linked to plasmid presence in serotypes c and e.
- Phages demonstrated successful adsorption and replication despite host-produced extracellular polysaccharides (mutan).
- Phages shared similar morphology (icosahedral heads, long noncontractile tails) and genome characteristics (linear dsDNA, 31-35 kb, 37-38% G+C).
- Restriction fragment patterns and DNA hybridization revealed significant sequence homology among the three phages, particularly between M102 and e10, and e10 and f1.
Conclusions:
- The characterized Streptococcus mutans phages are morphologically and genetically similar, suggesting a common ancestor.
- These phages represent potential candidates for phage therapy against Streptococcus mutans infections.
- Extracellular mutan does not impede phage activity, highlighting their potential efficacy in the oral environment.
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