biostudies-literatureUnknown13Wielento A<i>Porphyromonas gingivalis</i>, a keystone oral pathogen implicated in development and progression of periodontitis, may also contribute to the pathogenicity of diseases such as arthritis, atherosclerosis, and Alzheimer's. <i>P. gingivalis</i> is a master manipulator of host immune responses due to production of a large variety of virulence factors. Among these, <i>P. gingivalis</i> peptidilarginine deiminase (PPAD), an enzyme unique to <i>P. gingivalis</i>, converts C-terminal Arg residues in bacterium- and host-derived proteins and peptides into citrulline. PPAD contributes to stimulation of proinflammatory responses in host cells and is essential for activation of the prostaglandin E2 (PGE2) synthesis pathway in gingival fibroblasts. Since <i>P. gingivalis</i> is recognized mainly by TFrontiers in immunology823685https://www.ebi.ac.uk/biostudies/studies/S-EPMC9010743biostudies-literatureTLR2 Activation by <i>Porphyromonas gingivalis</i> Requires Both PPAD Activity and Fimbriae.PMC9010743Wielento ALagosz-Cwik KBGrabiec AMEick SBereta GPLamont RJPotempa JfalseTLR2 Activation by <i>Porphyromonas gingivalis</i> Requires Both PPAD Activity and Fimbriae.<i>Porphyromonas gingivalis</i>, a keystone oral pathogen implicated in development and progression of periodontitis, may also contribute to the pathogenicity of diseases such as arthritis, atherosclerosis, and Alzheimer's. <i>P. gingivalis</i> is a master manipulator of host immune responses due to production of a large variety of virulence factors. Among these, <i>P. gingivalis</i> peptidilarginine deiminase (PPAD), an enzyme unique to <i>P. gingivalis</i>, converts C-terminal Arg residues in bacterium- and host-derived proteins and peptides into citrulline. PPAD contributes to stimulation of proinflammatory responses in host cells and is essential for activation of the prostaglandin E2 (PGE2) synthesis pathway in gingival fibroblasts. Since <i>P. gingivalis</i> is recognized mainly by T2022-01-01T00:00:00Z20222025-04-05T13:24:41.711Z2025-04-05T13:24:41.711ZS-EPMC90107433543234210.3389/fimmu.2022.823685