Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis in young Chinese adults

Abstract

The aim of this study was to determine the presence or absence of Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis in young Chinese adults and to examine the A. actinomycetemcomitans isolates from positive subjects with regard to the serotype distribution, presence of the leukotoxin gene lktA and the promoter for the leukotoxin operon as well as the incidence of phage Aa phi 23. Sixty subjects, working in a knitting factory in the Province of Guangzhou, People's Republic of China, were investigated. Subgingival microbial samples were taken from both upper first molars. They were cultured both anaerobically and in 5% CO2. P. gingivalis was found in 33 subjects. On average, it constituted 7% of the total anaerobic cultivable counts. A. actinomycetemcomitans was detected in 37 subjects of which seven yielded counts > 10(5). Twenty-one subjects were positive for both organisms. A. actinomycetemcomitans serotype a was found in 9 subjects, serotype c was found in 23 and serotype e in 5. A. actinomycetemcomitans serotypes b and d were not detected in any subjects. Presence of the leukotoxin gene lktA was demonstrated for all A. actinomycetemcomitans isolates; however, none of the A. actinomycetemcomitans strains from the present study had a deletion in the promoter region of the leukotoxin operon. The results of this investigation show a high frequency of the putative periodontal pathogens P. gingivalis and A. actinomycetemcomitans and corroborate the concept that there is variation in virulence and pathogenic potential among isolates from different subjects.

Aggregatibacter actinomycetemcomitansand Its Relationship to Initiation of Localized Aggressive Periodontitis: Longitudinal Cohort Study of Initially Healthy Adolescents

“…This finding is not completely consistent with previous reports (14,35). However, in the studies that report A. actinomycetemcomitans isolation from the tongue, the subjects were much older and almost exclusively Asian and/or Caucasian (13,34).…”

Bleeding on probing differentially relates to bacterial profiles: the Oral Infections and Vascular Disease Epidemiology Study

“…The bacterial aetiology of periodontitis has been extensively studied and several putative causal microbes have been identified (Grossi et al 1994, Haffajee & Socransky 1994, Mombelli et al 1998, Socransky et al 1998, Van Winkelhoff et al 1999, Timmerman et al 2000, van der Velden et al 2006. However, much of the population-based research exploring relationships between bacteria and clinical periodontal disease uses pooled bacterial samples and defines bacterial exposure dichotomously by assessing the prevalence (presence/absence) of colonization at the patient level (Grossi et al 1994, Machtei et al 1999, Timmerman et al 2001, Van Winkelhoff et al 2002, van der Velden et al 2006.…”

Structural and Genetic Analyses of O Polysaccharide from Actinobacillus actinomycetemcomitans Serotype f

“…Different serotypes have been shown to be associated with periodontal health, periodontitis, and nonoral infections (1,2,7,17,65) and with different racial, ethnic, and geographic populations (18,19,20,30,31,32), suggesting that serotype-specific strain differences may be responsible for host specificity and virulence. The immunodominant outer membrane antigen of A. actinomycetemcomitans is located in the high-molecularmass O polysaccharide (O-PS) component of lipopolysaccharide (LPS) (6,38,49,58).…”