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Inducible bacteriophages of Actinobacillus actinomycetemcomitans

A Loftus1, A L Delisle

  • 1Department of Microbiology, School of Dentistry, University of Maryland at Baltimore 21201, USA.

Current Microbiology
|May 1, 1995
PubMed

Insights

Mitomycin C triggered phage induction in most Actinobacillus actinomycetemcomitans strains, revealing widespread lysogeny. Further analysis characterized these phages by DNA size and morphology.

Area of Science:

  • Microbiology
  • Bacteriology
  • Virology

Background:

  • Actinobacillus actinomycetemcomitans is a significant oral pathogen.
  • Bacteriophages, viruses that infect bacteria, can influence bacterial virulence and genetics.
  • Lysogeny, the state where a phage integrates into the host genome, is common in bacteria.

Purpose of the Study:

  • To investigate the prevalence of lysogeny in Actinobacillus actinomycetemcomitans.
  • To characterize the induced phages in terms of DNA, morphology, and infectivity.
  • To explore potential correlations between lysogeny and bacterial characteristics.

Main Methods:

  • Bacterial strains were treated with mitomycin C to induce phage production.
  • Phage DNA was analyzed using gel electrophoresis.
  • Phage morphology was examined via electron microscopy.
  • Curing experiments were performed to isolate nonlysogenic strains.

Main Results:

  • Mitomycin C induced cell lysis and phage production in most tested Actinobacillus actinomycetemcomitans strains.
  • Induced phages varied in DNA size and belonged to morphotypes A1 or B1.
  • No correlation was found between lysogeny and leukotoxin production or serotype.
  • Curing experiments confirmed the presence and infectivity of carried phages.

Conclusions:

  • Lysogeny is a widespread phenomenon in Actinobacillus actinomycetemcomitans.
  • The induced phages are diverse in terms of DNA and morphology.
  • Further research is needed to understand the role of phages in Actinobacillus actinomycetemcomitans biology.

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