Editorial Comments to the Special Issue: “Aggregatibacter actinomycetemcomitans—Gram-Negative Bacterial Pathogen”

Abstract

Aggregatibacter actinomycetemcomitans is a periodontal pathogen colonizing the oral cavity in many individuals of the human population. It is equipped with several potent virulence factors that can cause cell death and induce or evade the host inflammatory response. Both harmless and highly virulent genotypes of the bacterium have emerged because of the large genetic diversity within the species. The oral condition and age, as well as the geographic origin of the individual, influence the risk to be colonized by a virulent genotype of the bacterium. In the present editorial, the different genetic and virulence properties of A. actinomycetemcomitans will be addressed in relation to the publications in this Special Issue.

The composition of microbial communities in inflammatory periodontal diseases in young adults Tatars

“…Representatives of the Mogibacteriaceae family are among the subgingival phylotypes significantly enriched in subjects with gingivitis and periodontitis [21] , [32] , [33] . Although subgingival microbiota of adolescence with rapidly progressing periodontitis demonstrate high association with Aggregatibacter actinomycetemcomitans [10] , [23] , [30] , our 16S rRNA analysis did not show significant differences in abundance of Aggregatibacter between HC, GG and IP groups. Interestingly, previous study of subgingival biofilms from patients with rapidly progressing periodontitis in a Brazilian population demonstrated no association between A. actinomycetemcomitans and disease [34] .…”

“…Other bacterial species such as Prevotella intermedia, Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum, Selenomonas noxia , and Eubacterium nodatum are associated with periodontitis. Also, Selenomonas, Synergistes, Desulfobulbus, Eikenella corrodens, Peptostreptococcus micros, Campylobacter rectus , TM7 and Filifactor alocis are identified as possible periodontopathogens [3] , [5] , [7] , [17] , [30] . Genera Filifactor and Parvimonas , families Mogibacteriaceae and Porphyromonadaceae were significantly enriched in sites of subjects with GG and IP.…”

Quorum-quenching enzyme Est816 assisted antibiotics against periodontitis induced by Aggregatibacter actinomycetemcomitans in rats

“…A. actinomycetemcomitans can efficiently migrate through the gingival epithelium, inhibit bone collagen synthesis, and induce osteoblast apoptosis, thereby directly accelerating the progression of periodontitis ( Fives-Taylor et al., 1999 ; Herbert et al., 2016 ). The enhanced antibacterial ability of antibiotics inhibit A. actinomycetemcomitans , while A. actinomycetemcomitans employs virulence factors, such as ltxA , which protects it from phagocytosis and induces a pro-inflammatory response ( Oscarsson et al., 2020 ). Combination therapy decreases the release of virulence factors and MMP-9, thus indirectly restoring the imbalance in the host inflammatory response and resulting in a synergistic effect against periodontitis.…”