Temperate bacteriophages are common among Actinobacillus actinomycetemcomitans isolates from periodontal pockets

Abstract

Actinobacillus actinomycetemcomitans is a suspected etiologic agent in destructive periodontal diseases. The detection of bacteriophages in A. actinomycetemcomitans in the subgingival plaque of patients with rapidly destructive forms of periodontitis led to the hypothesis that bacteriophage infection might increase the virulence of this bacterium (19). A. actinomycetemcomitans was isolated from 68 subjects from the Netherlands and Switzerland with localized juvenile periodontitis, rapidly progressing periodontitis, or adult periodontitis, and was tested for the presence of temperate bacteriophage with the overlay plate technique. More than half of the A. actinomycetemcomitans strains were found to release bacteriophage which formed individual plaques on indicator strains. Electron microscopy of preparations from 7 strains revealed virions with an icosahedral head and a contractile tail typical for double-stranded DNA bacteriophages. The presence of A. actinomycetemcomitans carrying temperate bacteriophage was not correlated with the composition of the subgingival microflora nor with the clinical form of periodontal disease. Destructive periodontal disease of subjects with phage-carrying A. actinomycetemcomitans was not more severe than of subjects with phage-free A. actinomycetemcomitans as determined by several clinical parameters. In contrast, the pocket depth and the attachment loss were significantly lower for adult periodontitis subjects with phage-carrying A. actinomycetemcomitans. It seems unlikely that the frequently occurring temperate bacteriophages increase significantly the virulence of A. actinomycetemcomitans.

Enumeration of Porphyromonas gingivalis, Prevotella intermedia and Actinobacillus actinomycetemcomitans in subgingival plaque samples by a quantitative-competitive PCR method

“…Among the subgingival bacterial species identi®ed so far, Porphyromonas gingivalis, Prevotella intermedia and Actinobacillus actinomycetemcomitans have been associated with progressive adult periodontitis [2]. A. actinomycetemcomitans is infrequently found in periodontally healthy individuals [3], whereas Pr. intermedia has been found in healthy subjects and is more frequent in patients with periodontal diseases [4].…”

Transduction of antibiotic resistance markers among Actinobacillus actinomycetemcomitans strains by temperate bacteriophages Aa ? 23

“…The presence of prophage was tested in two ways. Transductants were screened for phage release by the overlay plate technique as previously described [9]. Additionally, the transductants were tested for the presence of AaST1 or Aa23 DNA in chromosomal Southern blot hybridizations.…”

“…Three morphologically distinct phages were demonstrated in periodontal pockets of a few patients [8]. Temperate bacteriophages were detected in more than 50% of the Aa isolates sampled from subgingival plaques of periodontitis patients [9]. A comparison of…”

Horizontal Gene Transfer in Plasmid: Are We Close to Eliminating Periodontal Pathogens?

“…Studies on saliva have isolated bacteriophages with a) bactericidal effect against specific bacterial pathogens such as Enterococcus faecalis, for example (Stevens et al 2009) and b) transduction property capable of transferring antibiotic resistance genes. The example includes temperate bacteriophage that transfers genes among Actinobacillus actinomycetemcomitans strains (Sandmeier et al 1995, Roy 2015.…”