Clonal distribution of natural competence in Actinobacillus actinomycetemcomitans.
The competence for natural transformation was investigated in 67 Actinobacillus actinomycetemcomitans strains. The transformation assays were performed with both cloned DNA fragments and chromosomal markers of A. actinomycetemcomitans. Competence was found in 12 of 18 serotype a strains, 0 of 21 serotype b strains, 0 of 14 serotype c strains, 3 of 6 serotype d strains, 3 of 4 serotype e strains, 0 of 3 serotype f strains, and 0 of 1 nonserotypeable strain. The transformation frequencies varied from 5 x 10(-3) to 4 x 10(-6) (median 1.5 x 10(-4)). The distribution pattern of natural competence is concordant with the major clonal lineages of A. actinomycetemcomitans. Serotype a strains are predominantly competent for transformation, while serotypes b and c strains are apparently non-competent.
Division of Primary Oral Health Care, University of Southern California School of Dentistry, Los Angeles, California 90089, USA.
O
O
Fujise
L
L
Lakio
Y
Y
Wang
S
S
Asikainen
C
C
Chen
D016976:Aggregatibacter actinomycetemcomitans / Q000235:genetics*; D002999:Clone Cells; D006801:Humans; D010518:Periodontitis / Q000382:microbiology*; D012703:Serotyping; D014169:Transformation, Bacterial