title: Plasmids in Actinobacillus actinomycetemcomitans strains isolated from periodontal lesions of patients with rapidly destructive periodontitis.
abstract: Several strains of Actinobacillus actinomycetemcomitans newly isolated from periodontal lesions of patients with rapidly destructive periodontitis were all shown to possess identical plasmid profiles consisting of 4 plasmids. The largest plasmid, 20 MegaDalton (MDa), was also found in reference strains. Two different methods were used for isolation of the plasmids; the large 20 MDa plasmid (pHRP1) was found using the Kado and Liu method only. The 3 small plasmids of 7.0, 5.2 and 4.0 MDa (pHRP2, pHRP3, pHRP4), respectively, were seen using the Birnboim and Doly method. These plasmids are so far to be regarded as cryptic; no phenotypical characters have been linked to their presence. The large 20 MDa plasmid was found in all strains examined, and may be a genotypical marker for the A. actinomycetemcomitans species.
authors.forename: B
authors.initials: B
authors.lastname: Olsvik
authors.forename: H R
authors.initials: HR
authors.lastname: Preus
mesh_terms: D000188:Actinobacillus / Q000235:genetics* / Q000302:isolation & purification; D006801:Humans; D010518:Periodontitis / Q000382:microbiology*; D010957:Plasmids