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Trends in Microbiology Apr 2021
Topics: Bacteroidaceae Infections; Gingipain Cysteine Endopeptidases; Humans; Porphyromonas gingivalis
PubMed: 33546976
DOI: 10.1016/j.tim.2021.01.010 -
International Journal of Oral Science Sep 2021Ulcerative Colitis (UC) has been reported to be related to Porphyromonas gingivalis (P. gingivalis). Porphyromonas gingivalis peptidylarginine deiminase (PPAD), a...
Ulcerative Colitis (UC) has been reported to be related to Porphyromonas gingivalis (P. gingivalis). Porphyromonas gingivalis peptidylarginine deiminase (PPAD), a virulence factor released by P. gingivalis, is known to induce inflammatory responses. To explore the pathological relationships between PPAD and UC, we used homologous recombination technology to construct a P. gingivalis strain in which the PPAD gene was deleted (Δppad) and a Δppad strain in which the PPAD gene was restored (comΔppad). C57BL/6 mice were orally gavaged with saline, P. gingivalis, Δppad, or comΔppad twice a week for the entire 40 days (days 0-40), and then, UC was induced by dextran sodium sulfate (DSS) solution for 10 days (days 31-40). P. gingivalis and comΔppad exacerbated DDS-induced colitis, which was determined by assessing the parameters of colon length, disease activity index, and histological activity index, but Δppad failed to exacerbate DDS-induced colitis. Flow cytometry and ELISA revealed that compared with Δppad, P. gingivalis, and comΔppad increased T helper 17 (Th17) cell numbers and interleukin (IL)-17 production but decreased regulatory T cells (Tregs) numbers and IL-10 production in the spleens of mice with UC. We also cocultured P. gingivalis, Δppad, or comΔppad with T lymphocytes in vitro and found that P. gingivalis and comΔppad significantly increased Th17 cell numbers and decreased Treg cell numbers. Immunofluorescence staining of colon tissue paraffin sections also confirmed these results. The results suggested that P. gingivalis exacerbated the severity of UC in part via PPAD.
Topics: Animals; Colitis, Ulcerative; Mice; Mice, Inbred C57BL; Porphyromonas gingivalis; Protein-Arginine Deiminases; Virulence Factors
PubMed: 34593756
DOI: 10.1038/s41368-021-00136-2 -
International Journal of Molecular... Feb 2021Human oral and gut microbiomes are crucial for maintenance of homeostasis in the human body. , the key etiologic agent of chronic periodontitis, can cause dysbiosis in...
Human oral and gut microbiomes are crucial for maintenance of homeostasis in the human body. , the key etiologic agent of chronic periodontitis, can cause dysbiosis in the mouth and gut, which results in local and systemic infectious inflammatory diseases. Our previous work resulted in extensive biochemical and functional characterization of one of the major heme acquisition systems (Hmu), with the leading role played by the HmuY hemophore-like protein. We continued our studies on the homologous heme acquisition protein (Bvu) expressed by the dominant species of the gut microbiome. Results from spectrophotometric experiments showed that Bvu binds heme preferentially under reducing conditions using Met145 and Met172 as heme iron-coordinating ligands. Bvu captures heme bound to human serum albumin and only under reducing conditions. Importantly, HmuY is able to sequester heme complexed to Bvu. This is the first study demonstrating that expresses a heme-binding hemophore-like protein, thus increasing the number of members of a novel HmuY-like family. Data gained in this study confirm the importance of HmuY in the context of survival in regard to its ability to cause dysbiosis also in the gut microbiome.
Topics: Bacterial Proteins; Bacteroides; Heme; Humans; Porphyromonas gingivalis; Protein Binding
PubMed: 33668119
DOI: 10.3390/ijms22052237 -
Periodontology 2000 2002
Review
Topics: Aggregatibacter actinomycetemcomitans; Anti-Bacterial Agents; Bacterial Adhesion; Bacteroides; Biofilms; Dental Plaque; Dental Prosthesis; Humans; Periodontal Diseases; Porphyromonas gingivalis; Prosthesis-Related Infections; Subgingival Curettage
PubMed: 12013340
DOI: 10.1034/j.1600-0757.2002.280102.x -
Frontiers in Cellular and Infection... 2022Autophagy is an immune homeostasis process induced by multiple intracellular and extracellular signals. Inflammation is a protective response to harmful stimuli such as... (Review)
Review
Autophagy is an immune homeostasis process induced by multiple intracellular and extracellular signals. Inflammation is a protective response to harmful stimuli such as pathogen microbial infection and body tissue damage. infection elicits both autophagy and inflammation, and dysregulation of autophagy and inflammation promotes pathology. This review focuses on the interaction between autophagy and inflammation caused by infection, aiming to elaborate on the possible mechanism involved in the interaction.
Topics: Autophagy; Homeostasis; Humans; Inflammation; Porphyromonas gingivalis
PubMed: 35846745
DOI: 10.3389/fcimb.2022.892610 -
Molecular Oral Microbiology Apr 2018
Topics: Biofilms; Community Participation; Hemoglobins; Humans; Lipopolysaccharides; Mouth; Periodontitis; Porphyromonas gingivalis; Virulence
PubMed: 29461020
DOI: 10.1111/omi.12218 -
Microbial Pathogenesis May 2016Porphyromonas gingivalis is deeply involved in the pathogenesis of marginal periodontitis, and recent findings have consolidated its role as an important and unique... (Review)
Review
Porphyromonas gingivalis is deeply involved in the pathogenesis of marginal periodontitis, and recent findings have consolidated its role as an important and unique pathogen. This bacterium has a unique dual lifestyle in periodontal sites including subgingival dental plaque (biofilm) and gingival cells, as it has been clearly shown that P. gingivalis is able to exert virulence using completely different tactics in each environment. Inter-bacterial cross-feeding enhances the virulence of periodontal microflora, and such metabolic and adhesive interplay creates a supportive environment for P. gingivalis and other species. Human oral epithelial cells harbor a large intracellular bacterial load, resembling the polymicrobial nature of periodontal biofilm. P. gingivalis can enter gingival epithelial cells and pass through the epithelial barrier into deeper tissues. Subsequently, from its intracellular position, the pathogen exploits cellular recycling pathways to exit invaded cells, by which it is able to control its population in infected tissues, allowing for persistent infection in gingival tissues. Here, we outline the dual lifestyle of P. gingivalis in subgingival areas and its effects on the pathogenesis of periodontitis.
Topics: Animals; Biofilms; Gingiva; Humans; Periodontitis; Porphyromonas gingivalis
PubMed: 26456558
DOI: 10.1016/j.micpath.2015.10.003 -
Infection and Immunity Jul 2018The keystone periodontal pathogen produces phosphorylated dihydroceramide lipids (sphingolipids) such as phosphoethanolamine dihydroceramide (PE DHC) and... (Review)
Review
The keystone periodontal pathogen produces phosphorylated dihydroceramide lipids (sphingolipids) such as phosphoethanolamine dihydroceramide (PE DHC) and phosphoglycerol dihydroceramide (PG DHC) lipids. Phosphorylated DHCs (PDHCs) from can affect a number of mammalian cellular functions, such as potentiation of prostaglandin secretion from gingival fibroblasts, promotion of RANKL-induced osteoclastogenesis, promotion of apoptosis, and enhancement of autoimmunity. In , these lipids affect anchoring of surface polysaccharides, resistance to oxidative stress, and presentation of surface polysaccharides (anionic polysaccharides and K-antigen capsule). In addition to phosphorylated dihydroceramide lipids, serine dipeptide lipids of are implicated in alveolar bone loss in chronic periodontitis through interference with osteoblast differentiation and function and promotion of osteoclast activity. As a prerequisite for designation as bacterial virulence factors, bacterial sphingolipids and serine dipeptide lipids are recovered in gingival/periodontal tissues, tooth calculus, human blood, vascular tissues, and brain. In addition to , other bacteria of the genera , , , , and produce sphingolipids and serine dipeptide lipids. The contribution of PDHCs and serine dipeptide lipids to the pathogenesis of periodontal and extraoral diseases may be an underappreciated area in microbe-host interaction and should be more intensively investigated.
Topics: Alveolar Bone Loss; Ceramides; Chronic Periodontitis; Humans; Lipopeptides; Osteoclasts; Phosphorylation; Porphyromonas gingivalis; Toll-Like Receptor 2; Virulence Factors
PubMed: 29632248
DOI: 10.1128/IAI.00035-18 -
Journal of Periodontal Research Feb 2009Research on Porphyromonas gingivalis, a periodontopathogen, has provided a tremendous amount of information over the last 20 years, which may exceed in part than that on... (Comparative Study)
Comparative Study Review
BACKGROUND AND OBJECTIVE
Research on Porphyromonas gingivalis, a periodontopathogen, has provided a tremendous amount of information over the last 20 years, which may exceed in part than that on other closely related members in terms of phylogenetic as well as proteomic criteria, including Bacteroides fragilis and B. thetaiotaomicron as major anaerobic, opportunistic pathogens in the medical field. In this minireview, we focused on recent research findings concerning surface components such as outer membrane proteins and fimbriae, of P. gingivalis.
MATERIAL AND METHODS
Elucidation of the surface components in P. gingivalis was especially difficult because outer membrane proteins are tightly bound to lipopolysaccharide and they are resistant to dissociation and separation from each other, even during sodium dodecyl sulfate-polyacrylamide gel electrophoresis, unless samples are appropriately heated. In addition, P. gingivalis is asaccharolytic and therefore a potent proteolytic bacterium, another factor causing difficulty in research. The study of the surface components was carefully carried out considering these unique features in P. gingivalis when compared with other gram-negative bacteria, including Escherichia coli and Pseudomonas aeruginosa.
RESULTS
Separation of outer membrane proteins, and characterization of OmpA-like proteins and RagAB as major proteins, is described herein. Our recent findings on FimA and Mfa1 fimbriae, two unique appendages in this organism, and on their regulation of expression are also described briefly.
CONCLUSION
Surface components of P. gingivalis somehow have contact with host tissues and cells because of the outermost cell elements. Therefore, such bacterial components are potentially important in the occurrence of periodontal diseases.
Topics: Bacterial Outer Membrane Proteins; Bacterial Proteins; Bacteroides; Fimbriae Proteins; Fimbriae, Bacterial; Humans; Phylogeny; Pili, Sex; Porphyromonas gingivalis; Proteome
PubMed: 18973529
DOI: 10.1111/j.1600-0765.2008.01135.x -
Future Microbiology 2015Porphyromonas gingivalis is one of the keystone pathogens associated with chronic periodontitis. All P. gingivalis strains examined thus far produce outer membrane... (Review)
Review
Porphyromonas gingivalis is one of the keystone pathogens associated with chronic periodontitis. All P. gingivalis strains examined thus far produce outer membrane vesicles. Recent studies have found that vesicles possess some well-known virulence factors of P. gingivalis such as adhesins, toxins and proteolytic enzymes. Carrying most of the characteristic features of their parent P. gingivalis cells, vesicles communicate with host cells and other members of microbial biofilms, resulting in the transmission of virulence factors into these host cells and the formation of pathogenic bacteria-dominated microbial communities. An in-depth understanding of both the nature and role of vesicles in the pathogenicity of P. gingivalis is both important and timely, particularly when speaking of periodontitis and its related systemic effects.
Topics: Adhesins, Bacterial; Biofilms; Humans; Microbial Consortia; Organelle Biogenesis; Periodontitis; Porphyromonas gingivalis; Transport Vesicles; Virulence Factors
PubMed: 26343879
DOI: 10.2217/fmb.15.63