The Quorum Sensing Mechanism of Aggregatibacter actinomycetemcomitans in Pathogenesis of Periodontitis: Systematic Literature Review

Background: Periodontitis is one of the most prevalent oral diseases worldwide and a significant public health concern. Periodontitis characterized by inflammation of the tissues supporting the teeth. It is primarily caused by bacteria in the subgingival biofilm, with A. actinomycetemcomitans and P. gingivalis as a key pathogens. These bacteria contribute to oral dysbiosis, leading to periodontal tissue damage. A. actinomycetemcomitans is particularly virulent, utilizing quorum sensing (QS) to regulate biofilm formation and enhance its pathogenicity, playing a significant role in the development and progression of periodontitis. Objective: This study aims to explain the quorum sensing mechanism in the pathogenesis of periodontitis caused by A. actinomycetemcomitans. Methods: This study employed a systematic literature review design by searching for articles based on predetermined inclusion and exclusion criteria. The search strategy used keywords and boolean operators across three databases (PubMed, Ebsco, ScienceDirect). Results: The variation between wild-type (Aa-WT) and LuxS mutant (Aa-LuxS) strains of A. actinomycetemcomitans impacts its pathogenicity. Quorum sensing (QS) interactions between A. actinomycetemcomitans and other periodontopathogens (P. gingivalis, T. denticola, P. intermedia) amplify virulence, promoting biofilm formation and disease progression. AI-2 regulates key processes, underscoring A. actinomycetemcomitans significant role in periodontitis. Conclusion: The quorum sensing mechanism in A. actinomycetemcomitans, through AI-2 production, is essential for microbial communication and biofilm formation, influencing the bacterium's virulence and role in periodontitis.