Comparison of Fusobacterium nucleatum and Porphyromonas gingivalis_
| Feature | Fusobacterium nucleatum | Porphyromonas gingivalis |
|---|---|---|
| Cell Morphology | Long, spindle-shaped rod (Chen et al. 2022) | Short rod (coccobacillus) (Lamont and Jenkinson 2000) |
| Gram Stain | Gram-negative (Shao et al. 2021) | Gram-negative (Shah and Collins 1988; How et al. 2016) |
| Oxygen Requirements | Obligate anaerobe (Shao et al. 2021) | Obligate anaerobe (Shah and Collins 1988; How et al. 2016) |
| Motility | Non-motile (Bolstad et al. 1996) | Non-motile (Shah and Collins 1988; How et al. 2016) |
| Production of pathognomonic enzymes or chemoattractants | Produces short chain fatty acids (SCFAs), e.g. acetate and butyrate (Dahlstrand Rudin et al. 2021). | Produces proteases (gingipains) (Singh et al. 2011; Jia et al. 2019) |
| Key Virulence Factors | Adhesins (FadA) (Chen et al. 2022), endotoxin (LPS) (Shao et al. 2021) | Gingipains, LPS, fimbriae (Singh et al. 2011; Jia et al. 2019) |
| Role in Diseases | Periodontal disease (Chen et al. 2022), colorectal cancer (Galasso et al. 2025), preterm birth (Shao et al. 2021), endometriosis (Muraoka et al. 2023) | Periodontal disease (Shah and Collins 1988; How et al. 2016), cardiovascular disease (Xie et al. 2020), rheumatoid arthritis (ahmadi et al. 2023), Alzheimer’s Disease (Kanagasingam et al. 2020) |
| Natural Habitat (Niche) | Human oral cavity (Chen et al. 2022), gut (Galasso et al. 2025), placenta (Wang et al. 2013; Chen et al. 2022) | Oral cavity, subgingival plaque (Horvat Aleksijević et al. 2022) |
| Clinical Significance | Involved in polymicrobial infections, biofilm formation (Chen et al. 2022; Horvat Aleksijević et al. 2022) | Major pathogen in periodontitis (Horvat Aleksijević et al. 2022), linked to systemic diseases (Xie et al. 2020; Horvat Aleksijević et al. 2022; ahmadi et al. 2023) |
| Drug Resistance | Some resistance to beta-lactams (presence of β-lactamase-producing strains) (Bolstad et al. 1996) | Limited resistance to beta-lactams, resistance to macrolides (Conrads et al. 2021) |
| Capsule | Occasionally has a present capsule (Bolstad et al. 1996) | Has a polysaccharide capsule (Singh et al. 2011) |
The mechanisms promoting carcinogenesis of F_ nucleatum and P_ gingivalis_
| Mechanism | Trigger factor | Explanation |
|---|---|---|
| Promotion of chronic inflammation | IL-6 (Gallimidi et al. 2015), IL-8 (Ha et al. 2016; Harrandah et al. 2020), TNF-α (Gallimidi et al. 2015; Liu et al. 2020) | Pro-inflammatory cytokines create a tumorfriendly microenvironment, promoting mutations and uncontrolled cell proliferation. |
| P. gingivalis: IL-1R2, IL-18 (Liu et al. 2020) | ||
| F.nucleatum : IL-1β (Aral et al. 2020), TGF-β (Abdulkareem et al. 2017) | ||
| Modulation of the immune response | Disruption of immune signaling (Wang and Ohura 2002; How et al. 2016; Bi et al. 2023) | Bacteria evade immune responses, leading to persistent infections and immune suppression. |
| Activation of the signal pathways associated with cancer development | NF-κB (Inaba et al. 2013; Gallimidi et al. 2015) | These pathways stimulate tumor growth, enhance survival and contribute to metastasis. |
| F.nucleatum: Wnt/NFAT (Da et al. 2021), STAT3 (Harrandah et al. 2020) | ||
| Increased invasion and metastasis | Epithelial-Mesenchymal Transition (EMT) (Ha et al. 2015; Harrandah et al. 2020), Matrix metalloproteinases (MMPs) (Gallimidi et al. 2015; Ha et al. 2016; Harrandah et al. 2020) | EMT enables cancer cells to detach and spread, while MMPs degrade the extracellular matrix, aiding metastasis. |
| Production of toxins and factors supporting tumor growth | Gingipains (P. gingivalis) (How et al. 2016; Bi et al. 2023), FadA (F. nucleatum) (Chen et al. 2022) | Gingipains disrupt cellular homeostasis, and FadA binds to E-cadherin, increasing epithelial permeability and promoting cancer progression. |
| Microbiota dysbiosis | Dysbiosis (Horvat Aleksijević et al. 2022; Cai et al. 2024) | Both bacteria contribute to changes in the microbiome, which promotes the proliferation of pathogenic microorganisms and increases the risk of developing cancer. |