TABLE 2.
Major virulence determinants of Porphyromonas gingivalisa
| Virulence determinants | Function |
|---|---|
| FimA | Adherence to biotic and abiotic surfaces; binding to salivary proteins, epithelial cells, fibrinogen, fibronectin, lactoferrin, erythrocytes, oral streptococci; binding of chemokine (C-X-C motif) receptor 4 to suppress toll-like receptor 2/1-mediated proinflammatory and antimicrobial responses; binding of complement receptor 3 to inhibit interleukin-12 production to promote intracellular survival of bacteria, without affecting tumor necrosis factor-alpha-mediated destructive inflammation |
| Mfa1 pili | Adherence to oral streptococci; binding to dendritic cell-specific intercellular adhesion molecule-3 grabbing nonintegrin of dendritic cells to initiate the entry and the survival of the bacteria |
| Hemagglutinins HagA, B, and C | Hemolysis for iron acquisition as a nutrient; adherence to epithelial cells; induction of platelet aggregation |
| Hemoglobulin binding protein | Binding of hemoglobin for nutrient acquisition |
| Gingipains (RgpA, RgpB, Kgp) | Degradation of host tissue and antibodies; activation of the complement system, or inactivation of the complement system by degradation of its components; generating C5a to initiate C5aR toll-like receptor-2 crosstalk to promote bacterial survival in neutrophils and macrophages; degradation of toll-like coreceptors to suppress immune response |
| Capsule | Antiphagocytosis |
| Lipid A of lipopolysaccharide | Weak agonist or antagonist of toll-like receptor-4 to induce or inhibit inflammatory response |
| Phosphoserine phosphatase SerB | Suppress interleukin-8 production to induce host defense paralysis |