title: Actinobacillus actinomycetemcomitans serotype e--biotypes, genetic diversity and distribution in relation to periodontal status.
abstract: Actinobacillus actinomycetemcomitans isolates from 356 individuals were screened for identification of serotype e in order to investigate its distribution in relation to periodontal status. From subjects with serotype e, 1-6 isolates per subject (n = 61) were genotyped using arbitrarily primed-polymerase chain reaction (AP-PCR) and apaH gene polymerase chain reaction-restriction fragment-length polymorphism (PCR-RFLP) analysis to determine the genetic heterogeneity within the serotype. Furthermore, one serotype e strain per subject was tested for fermentation of 8 carbohydrates for biotyping. Among patients with adult periodontitis (n = 219), localized juvenile periodontitis (n = 55) and other forms of early-onset periodontitis (n = 18) serotypes b, a and c, respectively, were the most frequently detected serotypes. Non-periodontitis subjects (n = 64) were predominantly colonized with serotype c. Serotype e was found in 30 (14%) adult periodontitis patients, 2 (11%) early-onset periodontitis patients and in 5 (8%) non-periodontitis individuals, but in none of the 55 localized juvenile periodontitis patients. AP-PCR distinguished 3 and apaH gene PCR-RFLP analysis 2 genotypes among the 61 A. actinomycetemcomitans serotype e isolates, one genotype per subject. The AP-PCR genotypes 1 and 3 represented the apaH genotype 1 and the AP-PCR genotype 2 the apaH genotype 2. On the basis of variable fermentation of galactose and xylose, 3 biotypes among A. actinomycetemcomitans serotype e were established. Contrary to the absence of A. actinomycetemcomitans serotype e in localized juvenile periodontitis patients, its detection frequency was comparable among other forms of periodontitis and periodontal health. Clinical serotype e isolates form at least 2 genetic types and 3 biotypes.
authors.affiliation: Department of Pedodontics and Orthodontics, University of Helsinki, Finland.
authors.forename: B
authors.initials: B
authors.lastname: Doğan
authors.forename: M H
authors.initials: MH
authors.lastname: Saarela
authors.forename: H
authors.initials: H
authors.lastname: Jousimies-Somer
authors.forename: S
authors.initials: S
authors.lastname: Alaluusua
authors.forename: S
authors.initials: S
authors.lastname: Asikainen
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016976:Aggregatibacter actinomycetemcomitans / Q000145:classification* / Q000235:genetics*; D010520:Aggressive Periodontitis / Q000175:diagnosis / Q000382:microbiology; D015373:Bacterial Typing Techniques; D016009:Chi-Square Distribution; D002648:Child; D002675:Child, Preschool; D014644:Genetic Variation; D005838:Genotype; D006801:Humans; D008875:Middle Aged; D010518:Periodontitis / Q000175:diagnosis / Q000382:microbiology*; D012150:Polymorphism, Restriction Fragment Length; D019105:Random Amplified Polymorphic DNA Technique; D012703:Serotyping