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Frontiers in Cellular and Infection... 2023
Topics: Humans; Porphyromonas gingivalis; Immune Evasion; Dysbiosis; Periodontal Diseases
PubMed: 37842000
DOI: 10.3389/fcimb.2023.1289103 -
Clinical and Experimental Dental... Aug 2022The Gram-negative anaerobic rod Porphyromonas gingivalis (P. gingivalis) is regarded as a keystone pathogen in periodontitis and expresses a multitude of virulence...
OBJECTIVES
The Gram-negative anaerobic rod Porphyromonas gingivalis (P. gingivalis) is regarded as a keystone pathogen in periodontitis and expresses a multitude of virulence factors iincluding fimbriae that are enabling adherence to and invasion in cells and tissues. The progression of periodontitis is a consequence of the interaction between the host immune response and periodontal pathogens. The aim of this study was to investigate the genome-wide impact of recombinant fimbrial protein FimA from P. gingivalis W83 on the gene expression of oral squamous carcinoma cells by transcriptome analysis.
MATERIALS AND METHODS
Human squamous cell carcinoma cells (SCC-25) were stimulated for 4 and 24 h with recombinant FimA. RNA sequencing was performed and differential gene expression and enrichment were analyzed using gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and REACTOME. The results of transcriptome analysis were validated using quantitative real-time polymerase chain reaction (PCR) with selected genes.
RESULTS
Differential gene expression after 4 and 24 h revealed upregulation of 464 (4 h) and 179 genes (24 h) and downregulation of 69 (4 h) and 312 (24 h) genes. GO, KEGG, and REACTONE enrichment analysis identified a strong immunologic transcriptomic response signature after 4 h. After 24 h, mainly those genes were regulated, which belonged to cell metabolic pathways and replication. Real-time PCR of selected genes belonging to immune response and signaling demonstrated strong upregulation of CCL20, TNFAIP6, CXCL8, TNFAIP3, and NFkBIA after both stimulation times.
CONCLUSIONS
These data shed light on the RNA transcriptome of human oral squamous carcinoma epithelial cells following stimulation with P. gingivalis FimA and identify a strong immunological gene expression response to this virulence factor. The data provide a base for future studies of molecular and cellular interactions between P. gingivalis and oral epithelium to elucidate basic mechanisms that may provide new prospects for periodontitis therapy and give new insights into the development and possible treatments of cancer.
Topics: Carcinoma, Squamous Cell; Epithelial Cells; Fimbriae Proteins; Gene Expression; Humans; Immunity; Mouth Neoplasms; Periodontitis; Porphyromonas gingivalis
PubMed: 35570325
DOI: 10.1002/cre2.588 -
NPJ Biofilms and Microbiomes Jul 2022Microbial pathogens employ signaling systems through cyclic (di-) nucleotide monophosphates serving as second messengers to increase fitness during pathogenesis....
Microbial pathogens employ signaling systems through cyclic (di-) nucleotide monophosphates serving as second messengers to increase fitness during pathogenesis. However, signaling schemes via second messengers in Porphyromonas gingivalis, a key Gram-negative anaerobic oral pathogen, remain unknown. Here, we report that among various ubiquitous second messengers, P. gingivalis strains predominantly synthesize bis-(3',5')-cyclic di-adenosine monophosphate (c-di-AMP), which is essential for their growth and survival. Our findings demonstrate an unusual regulation of c-di-AMP synthesis in P. gingivalis. P. gingivalis c-di-AMP phosphodiesterase (PDE) gene (pde) positively regulates c-di-AMP synthesis and impedes a decrease in c-di-AMP concentration despite encoding conserved amino acid motifs for phosphodiesterase activity. Instead, the predicted regulator gene cdaR, unrelated to the c-di-AMP PDE genes, serves as a potent negative regulator of c-di-AMP synthesis in this anaerobe. Further, our findings reveal that pde and cdaR are required to regulate the incorporation of ATP into c-di-AMP upon pyruvate utilization, leading to enhanced biofilm formation. We show that shifts in c-di-AMP signaling change the integrity and homeostasis of cell envelope, importantly, the structure and immunoreactivity of the lipopolysaccharide layer. Additionally, microbe-microbe interactions and the virulence potential of P. gingivalis were modulated by c-di-AMP. These studies provide the first glimpse into the scheme of second messenger signaling in P. gingivalis and perhaps other Bacteroidetes. Further, our findings indicate that c-di-AMP signaling promotes the fitness of the residents of the oral cavity and the development of a pathogenic community.
Topics: Adenosine Monophosphate; Bacterial Proteins; Cyclic AMP; Dinucleoside Phosphates; Homeostasis; Phosphoric Diester Hydrolases; Porphyromonas gingivalis; Virulence
PubMed: 35794154
DOI: 10.1038/s41522-022-00316-w -
Journal of Microbiology and... May 2021() is a major bacterial pathogen that causes periodontitis, a chronic inflammatory disease of tissues around the teeth. Periodontitis is known to be related to other...
() is a major bacterial pathogen that causes periodontitis, a chronic inflammatory disease of tissues around the teeth. Periodontitis is known to be related to other diseases, such as oral cancer, Alzheimer's disease, and rheumatism. Thus, a precise and sensitive test to detect is necessary for the early diagnosis of periodontitis. The objective of this study was to optimize a rapid visual detection system for . First, we performed a visual membrane immunoassay using 3,3',5,5'-tetramethylbenzidine (TMB; blue) and coating and detection antibodies that could bind to the host laboratory strain, ATCC 33277. Antibodies against the surface adhesion molecules RgpB (arginine proteinase) and Kgp (lysine proteinase) were determined to be the most specific coating and detection antibodies, respectively. Using these two selected antibodies, the streptavidin-horseradish peroxidase (HRP) reaction was performed using a nitrocellulose membrane and visualized with a detection range of 10-10 bacterial cells/ml following incubation for 15 min. These selected conditions were applied to test other oral bacteria, and the results showed that could be detected without crossreactivity to other bacteria, including and . Furthermore, three clinical strains of , KCOM 2880, KCOM 2803, and KCOM 3190, were also recognized using this optimized enzyme immunoassay (EIA) system. To conclude, we established optimized conditions for detection with specificity, accuracy, and sensitivity. These results could be utilized to manufacture economical and rapid detection kits for .
Topics: Bacteriological Techniques; Colorimetry; Gingipain Cysteine Endopeptidases; Humans; Immunoenzyme Techniques; Limit of Detection; Periodontitis; Porphyromonas gingivalis
PubMed: 33820889
DOI: 10.4014/jmb.2103.03029 -
Immunobiology Nov 2012Signaling crosstalk between complement and Toll-like receptors (TLRs) normally serves to coordinate host immunity. However, the periodontal bacterium Porphyromonas... (Review)
Review
Signaling crosstalk between complement and Toll-like receptors (TLRs) normally serves to coordinate host immunity. However, the periodontal bacterium Porphyromonas gingivalis expresses C5 convertase-like enzymatic activity and adeptly exploits complement-TLR crosstalk to subvert host defenses and escape elimination. Intriguingly, this defective immune surveillance leads to the remodeling of the periodontal microbiota to a dysbiotic state that causes inflammatory periodontitis. Understanding the mechanisms by which P. gingivalis modulates complement function to cause dysbiosis offers new targets for complement therapeutics.
Topics: Bacteroidaceae Infections; Complement Activation; Complement C3-C5 Convertases; Complement System Proteins; Humans; Microbial Interactions; Periodontitis; Porphyromonas gingivalis; Signal Transduction; Toll-Like Receptors
PubMed: 22964237
DOI: 10.1016/j.imbio.2012.07.007 -
Microbiology (Reading, England) Nov 2019Key to onset and progression of periodontitis is a complex relationship between oral bacteria and the host. The organisms most associated with severe periodontitis are...
Key to onset and progression of periodontitis is a complex relationship between oral bacteria and the host. The organisms most associated with severe periodontitis are the periodontal pathogens of the red complex: , and . These organisms express sialidases, which cleave sialic acid from host glycoproteins, and contribute to disease through various mechanisms. Here, we expressed and purified recombinant sialidase SiaPG (PG_0352) and characterized its activity on a number of substrates, including host sialoglycoproteins and highlighting the inability to cleave diacetylated sialic acids - a phenomenon overcome by the NanS sialate-esterase from . Indeed SiaPG required NanS to maximize sialic acid harvesting from heavily O-acetylated substrates such as bovine salivary mucin, hinting at the possibility of interspecies cooperation in sialic acid release from host sources by these members of the oral microbiota. Activity of SiaPG and was inhibited using the commercially available chemotherapeutic zanamivir, indicating its potential as a virulence inhibitor, which also inhibited sialic acid release from mucin, and was capable of inhibiting biofilm formation of on oral glycoprotein sources. Zanamivir also inhibited attachment and invasion of oral epithelial cells by and other periodontal pathogens, both in monospecies but also in multispecies infection experiments, indicating potential to suppress host-pathogen interactions of a mixed microbial community. This study broadens our understanding of the multifarious roles of bacterial sialidases in virulence, and indicates that their inhibition with chemotherapeutics could be a promising strategy for periodontitis therapy.
Topics: Bacterial Proteins; Biofilms; Cell Line; Host-Pathogen Interactions; Humans; Microbial Interactions; Mucins; Mutation; Neuraminidase; Polysaccharides; Porphyromonas gingivalis; Recombinant Proteins; Sialoglycoproteins; Tannerella forsythia; Virulence Factors; Zanamivir
PubMed: 31517596
DOI: 10.1099/mic.0.000851 -
PLoS Pathogens Mar 2014Porphyromonas gingivalis and Treponema denticola are strongly associated with chronic periodontitis. These bacteria have been co-localized in subgingival plaque and...
Porphyromonas gingivalis and Treponema denticola are strongly associated with chronic periodontitis. These bacteria have been co-localized in subgingival plaque and demonstrated to exhibit symbiosis in growth in vitro and synergistic virulence upon co-infection in animal models of disease. Here we show that during continuous co-culture a P. gingivalis:T. denticola cell ratio of 6∶1 was maintained with a respective increase of 54% and 30% in cell numbers when compared with mono-culture. Co-culture caused significant changes in global gene expression in both species with altered expression of 184 T. denticola and 134 P. gingivalis genes. P. gingivalis genes encoding a predicted thiamine biosynthesis pathway were up-regulated whilst genes involved in fatty acid biosynthesis were down-regulated. T. denticola genes encoding virulence factors including dentilisin and glycine catabolic pathways were significantly up-regulated during co-culture. Metabolic labeling using 13C-glycine showed that T. denticola rapidly metabolized this amino acid resulting in the production of acetate and lactate. P. gingivalis may be an important source of free glycine for T. denticola as mono-cultures of P. gingivalis and T. denticola were found to produce and consume free glycine, respectively; free glycine production by P. gingivalis was stimulated by T. denticola conditioned medium and glycine supplementation of T. denticola medium increased final cell density 1.7-fold. Collectively these data show P. gingivalis and T. denticola respond metabolically to the presence of each other with T. denticola displaying responses that help explain enhanced virulence of co-infections.
Topics: Coculture Techniques; Coinfection; Microscopy, Electron, Scanning; Oligonucleotide Array Sequence Analysis; Porphyromonas gingivalis; Reverse Transcriptase Polymerase Chain Reaction; Symbiosis; Transcriptome; Treponema denticola
PubMed: 24603978
DOI: 10.1371/journal.ppat.1003955 -
Epidemiology and Infection May 2020Porphyromonas gingivalis has been linked to the development and progression of oesophageal squamous cell carcinoma (ESCC), and is considered to be a high-risk factor for...
Porphyromonas gingivalis has been linked to the development and progression of oesophageal squamous cell carcinoma (ESCC), and is considered to be a high-risk factor for ESCC. Currently, the commonly used methods for P. gingivalis detection are culture or DNA extraction-based, which are either time and labour intensive especially for high-throughput applications. We aimed to establish and evaluate a rapid and sensitive direct quantitative polymerase chain reaction (qPCR) protocol for the detection of P. gingivalis without DNA extraction which is suitable for large-scale epidemiological studies. Paired gingival swab samples from 192 subjects undergoing general medical examinations were analysed using two direct and one extraction-based qPCR assays for P. gingivalis. Tris-EDTA buffer-based direct qPCR (TE-direct qPCR), lysis-based direct qPCR (lysis-direct qPCR) and DNA extraction-based qPCR (kit-qPCR) were used, respectively, in 192, 132 and 60 of these samples for quantification of P. gingivalis. The sensitivity and specificity of TE-direct qPCR was 95.24% and 100% compared with lysis-direct qPCR, which was 100% and 97.30% when compared with kit-qPCR; TE-direct qPCR had an almost perfect agreement with lysis-direct qPCR (κ = 0.954) and kit-qPCR (κ = 0.965). Moreover, the assay time used for TE-direct qPCR was 1.5 h. In conclusion, the TE-direct qPCR assay is a simple and efficient method for the quantification of oral P. gingivalis and showed high sensitivity and specificity compared with routine qPCR.
Topics: Bacteriological Techniques; Humans; Polymerase Chain Reaction; Porphyromonas gingivalis; Sensitivity and Specificity
PubMed: 32418555
DOI: 10.1017/S0950268820001053 -
Virulence May 2014
Topics: Female; Heart Valves; Humans; Male; Periodontal Pocket; Porphyromonas gingivalis
PubMed: 24759693
DOI: 10.4161/viru.28930 -
Microbiology Spectrum Aug 2023Bacteria have to persist under low iron conditions in order to adapt to the nutritional immunity of a host. Since the knowledge of iron stimulon of is sparse, we...
Bacteria have to persist under low iron conditions in order to adapt to the nutritional immunity of a host. Since the knowledge of iron stimulon of is sparse, we examined oral (Porphyromonas gingivalis and Prevotella intermedia) and gut (Bacteroides thataiotaomicron) representatives for their ability to adapt to iron deplete and iron replete conditions. Our transcriptomics and comparative genomics analysis show that many iron-regulated mechanisms are conserved within the phylum. They include genes upregulated in low iron, as follows: (flavodoxin), (hemin uptake operon), and loci encoding ABC transporters. Downregulated genes were (ferredoxin), (rubrerythrin), (succinate dehydrogenase/fumarate reductase), (oxoglutarate oxidoreductase/dehydrogenase), and (pyruvate:ferredoxin/flavodoxin oxidoreductase). Some genus-specific mechanisms, such as the of B. thetaiotaomicron coding for carbohydrate metabolism and the coding for xenosiderophore utilization were also identified. While all bacteria tested in our study had the operon coding for nitrite reduction and were able to reduce nitrite levels present in culture media, the expression of the operon was iron dependent only in B. thetaiotaomicron. It is noteworthy that we identified a significant overlap between regulated genes found in our study and the B. thetaiotaomicron colitis study (W. Zhu, M. G. Winter, L. Spiga, E. R. Hughes et al., Cell Host Microbe 27:376-388, 2020, http://dx.doi.org/10.1016/j.chom.2020.01.010). Many of those commonly regulated genes were also iron regulated in the oral bacterial genera. Overall, this work points to iron being the master regulator enabling bacterial persistence in the host and paves the way for a more generalized investigation of the molecular mechanisms of iron homeostasis in . are an important group of anaerobic bacteria abundant both in the oral and gut microbiomes. Although iron is a required nutrient for most living organisms, the molecular mechanisms of adaptation to the changing levels of iron are not well known in this group of bacteria. We defined the iron stimulon of by examination of the transcriptomic response of Porphyromonas gingivalis and Prevotella intermedia (both belong to the oral microbiome) and Bacteroidetes thetaiotaomicron (belongs to the gut microbiome). Our results indicate that many of the iron-regulated operons are shared among the three genera. Furthermore, using bioinformatics analysis, we identified a significant overlap between our studies and transcriptomic data derived from a colitis study, thus underscoring the biological significance of our work. Defining the iron-dependent stimulon of can help to identify the molecular mechanisms of iron-dependent regulation as well as better understand the persistence of the anaerobes in the human host.
Topics: Humans; Bacteroidetes; Ferredoxins; Flavodoxin; Nitrites; Porphyromonas gingivalis; Iron; Iron Deficiencies; Colitis; Inflammation
PubMed: 37314331
DOI: 10.1128/spectrum.04733-22