Enterococcus faecalis adhesin, Ace, mediates attachment to particulate dentin

An enzyme linked immunosorbent assay was developed to assess E. faecalis adhesion to particulate dentin. E. faecalis, OG1RF, which expresses the collagen binding protein (Ace+), and a derivative of OG1RF, TX5256, deficient in the collagen binding protein (Ace-) were grown at 46 degrees C, necessary for in vitro expression of Ace, and at 37 degrees C. E. faecalis binding to dentin was measured at 0, 15, 30, 60, 120, and 360 minutes. Compared to TX5256 and OG1RF grown at 37 degrees C, OG1RF grown at 46 degrees C adhered significantly better at all time points except 15 minutes (p < 0.001) exhibiting maximum binding at 120 minutes (17.4% of a positive control). Type I collagen at 100 microg/ml inhibited dentin binding by OG1RF grown at 46 degrees C in both competition (p < 0.005) and displacement assays (p < 0.046). Immunoaffinity purified anti-Ace IgG at 200 microg of protein inhibited adhesion of OG1RF grown at 46 degrees C to dentin.