Table 2 Proteins and peptides secreted by atherosclerotic plaque-associated bacteria and their potential roles in disease aetiology
Microbes | Secreted proteins | Mol wt. (kDa) | Function | Reference |
|---|---|---|---|---|
A. actinomycetemcomitans | Leukotoxin (LtxA) | 114 | Targets leukocyte function antigen-1 on activated WBC triggering lysosomal-mediated cell death. | |
| Â | Cytolethal distending toxin (Cdt) | 31.5 | Inhibits macrophage phagocytosis and subverts cytokine production | |
C. pneumoniae | (CPAF) chlamydial protease-like or proteasome-like activity factor | 70 | Disrupts host MHC antigen presentation | |
E. corrodens | Corrodecin (bacteriocin) | 23.6 | Potential role at the periodontal site | |
|  | Hydrolytic enzymes (includes proline aminopeptidase, thiol-dependent haemolysin and esterase activities) | – | Proposed to act against proline residues in collagen, immunoglobulin and complement proteins | |
F. necrophorum | Leukotoxin (LktA) | 335.9 | Virulence factor | |
F. nucleatum | Fusolysin | 115 | – | |
H. pylori | CagA oncoprotein | 132.4 | Virulence factor. Reprograms gastric epithelial cells | |
| Â | VacA exotoxin (Vacuolating cytotoxin A) | 88 | Virulence factor | |
| Â | HP-NAP (neutrophil activating protein) | 204 | Activates innate immunity | |
| Â | CagL Y58/E59 (amino acid polymorphisms) | 26.8 | Increases hypochlorhydria; disrupts cell membrane integrity | |
| Â | Hpn | 7 | Modulates cytokine secretion | |
|  | Tip-α | 19.6 | Bacterial pathogenesis | |
H. pylori | HP0175 | 34 | Virulence factor | |
| Â | HcpE(HP0235) | 39.4 | Virulence factor | |
| Â | DupA (Duodenal ulcer producing) | 20 | Virulence factor | |
|  | HtrA (high temperature requirement—A) chaperones and serine protease | 48 | Virulence factor | |
P. endodontalis | 35,406 protease | 88 | Role in pathogenesis and nutrition of the microbe | |
P. gingivalis | Arginine gingipain | 81 | Regulates IL-8; modulates microbiome population | |
| Â | Lysine gingipain | 60 | Â | Â |
| Â | SerB protein | 45.9 | Entry and survival of P. gingivalis in the epithelial cells | |
| Â | Fimbrilin A | 43 | Hemagglutinating activity | |
P. intermedia | Interpain A | 27 | Potential virulence factor | |
P. aeruginosa | Alkaline protease | 50 | Suggested role in pathogenesis | |
| Â | (AprA) | 45.5 | Â | Â |
| Â | Elastase A (LasA) | 53.7 | Â | Â |
| Â | Elastase B (LasB) | 26 | Â | Â |
| Â | Protease IV | Â | Â | Â |
| Â | LepA (large exoprotease) | 66.3 | Activation of pro-inflammatory pathway | Â |
S. gordonii | A soluble GAPDH (glyceraldehyde 3-phosphate dehydrogenase) | 35.9 | Virulence factor | |
S. mitis | Mitilysin (cholesterol-dependant cytolysin) | 53 | Cholesterol-dependent cytolysin | |
S. mutans | CSP (competence-stimulating peptide) | 5.2 | Inhibits Candida albicans morphological switch, found in oral cavity | |
S. sanguinis | FruA (exo-beta-D-fructosidase) | 140 | Multifunctional enzyme | |
| Â | CD-14 binding protein | 190 | Stimulate cytokine synthesis | |
T. forsythia | Karilysin | 52 | Virulence factor | |
|  | KLIKK protease | – | Host protein degradation and pathogenicity | |
T. denticola | Dentipain (IdeT) cysteine protease | 43 | Virulence factor |
