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Electron microscopy of phages in serotypes of Actinobacillus actinomycetemcomitans

I Olsen1, E Namork, V Myhrvold

  • 1Section of Microbiology, Department of Oral Biology, Dental Faculty, University of Oslo, Norway.

Oral Microbiology and Immunology
|December 1, 1993
PubMed

Insights

Bacteriophages were detected in specific serotypes of Actinobacillus actinomycetemcomitans using electron microscopy. This finding was limited to certain serotypes and fresh clinical isolates, not older or related bacterial strains.

Area of Science:

  • Microbiology
  • Virology
  • Bacteriology

Background:

  • Actinobacillus actinomycetemcomitans and related species are significant in oral and systemic infections.
  • Bacteriophages, viruses that infect bacteria, can influence bacterial virulence and evolution.
  • Understanding phage presence in these bacteria is crucial for microbial research.

Purpose of the Study:

  • To investigate the presence of bacteriophages in various strains of Actinobacillus actinomycetemcomitans and related bacteria.
  • To determine if bacteriophage presence correlates with specific serotypes or isolate age.

Main Methods:

  • Transmission electron microscopy was employed to examine bacterial strains.
  • A panel of Actinobacillus, Haemophilus, and Pasteurella species and strains were analyzed.
  • Specific serotypes and clinical isolates of Actinobacillus actinomycetemcomitans were prioritized.

Main Results:

  • Bacteriophages were identified in serotype a (SUNY 75) and serotype e (UOH 1705) of Actinobacillus actinomycetemcomitans.
  • Phages were also detected in fresh clinical isolates UOH Q1243 and UOH Q1247 of A. actinomycetemcomitans.
  • No phages were found in serotypes b, c, and d of A. actinomycetemcomitans, nor in other tested related species or older strains.

Conclusions:

  • Bacteriophage presence is not universal across all Actinobacillus actinomycetemcomitans serotypes or related species.
  • Specific serotypes (a and e) and fresh clinical isolates of A. actinomycetemcomitans harbor bacteriophages.
  • Further research may explore the impact of these phages on A. actinomycetemcomitans biology and pathogenicity.

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