<i>L</i>. <i>plantarum</i> LTA interferes with sucrose decomposition and dextran-FITC binding to <i>S</i>. <i>mutans</i>.

<p><i>S</i>. <i>mutans</i> (1 × 10⁸ CFU/ml) was grown in BHI medium at 37°C for 24 h in the presence or absence of (A) Lp.LTA at the indicated concentrations and (B) Lp.LTA or Deala-Lp.LTA at 30 μg/ml. <i>S</i>. <i>mutans</i> exopolysaccharide was determined by flow cytometry using dextran-FITC. Percentage of exopolysaccharide-positive <i>S</i>. <i>mutans</i> is in histograms. One of the three similar results is shown. (C) <i>S</i>. <i>mutans</i> (1 × 10⁸ CFU/ml) was grown in BHI medium supplemented with 0.5% sucrose at 37°C for 24 h in the presence or absence of Lp.LTA (10, 30, or 50 μg/ml). The culture supernatants were subjected to HPLC-RID for sucrose detection. Data are mean values ± S.D. of triplicate samples. Asterisks indicate significant difference at <i>P</i> < 0.05 compared with non-treatment control group.</p

<i>L</i>. <i>plantarum</i> LTA inhibits <i>S</i>. <i>mutans</i> biofilm formation.

<p><i>S</i>. <i>mutans</i> (1 × 10⁸ CFU/ml) was grown on 96-well polystyrene plates at 37°C for 24 h in the presence or absence of (A) <i>L</i>. <i>plantarum</i> culture supernatant (Lp.sup) at the indicated concentrations; (B) 20% of Lp.sup, proteinase K-treated Lp.sup (ProK-Lp.sup), or heat-treated Lp.sup (Heat-Lp.sup); (C) 20% of Lp.sup or octyl-sepharose beads-treated Lp.sup (Octyl beads-Lp.sup); (D) 30 μg/ml of <i>L</i>. <i>plantarum</i> LTA (Lp.LTA), <i>L</i>. <i>plantarum</i> lipoprotein (Lp.LPP), <i>L</i>. <i>plantarum</i> peptidoglycan (Lp.PGN), MDP, or Tri-DAP. Biofilm formation extent was determined by a crystal violet assay. Data are mean values ± S.D. of triplicate samples. Asterisk, significant induction at <i>P</i> < 0.05 compared with non-treatment control group.</p

<i>L</i>. <i>plantarum</i> LTA inhibits biofilm formation of various <i>S</i>. <i>mutans</i> strains.

<p>(A) <i>S</i>. <i>mutans</i> (1 × 10⁸ CFU/ml) was grown on 96-well polystyrene plates at 37°C for 24 h in the presence or absence of Lp.LTA, <i>Lactobacillus sakei</i> LTA (Ls.LTA), <i>Lactobacillus delbrueckii</i> LTA (Ld.LTA), or <i>Lactobacillus rhamnosus GG</i> LTA (Lgg.LTA) at the indicated concentrations. <i>S</i>. <i>mutans</i> (B) Ingbritt, (C) OMZ-65, (D) LM-7, (E) KCOM1197, or (F) KCOM1214 was cultured on 96-well polystyrene plates at 37°C for 24 h with Lp.LTA at 10 or 30 μg/ml. Biofilm formation extent was determined by the crystal violet assay. Data are mean values ± S.D. of triplicate samples. Asterisks, significant induction at <i>P</i> < 0.05 compared with non-treatment control group.</p

<i>L</i>. <i>plantarum</i> LTA inhibits biofilm formation and aggregation of <i>S</i>. <i>mutans</i> in dental biofilm models.

<p>(A) <i>S</i>. <i>mutans</i> (1 × 10⁸ CFU/ml) was grown in glass bottom dishes at 37°C for 24 h in the presence or absence of Lp.LTA at 3, 10, or 30 μg/ml. Lp.LTA-treated <i>S</i>. <i>mutans</i> biofilms were observed by confocal laser scanning microscopy (green, SYTO9; red, propidium iodide). (B-D) <i>S</i>. <i>mutans</i> (1 × 10⁸ CFU/ml) was grown on (B) 24-well polystyrene plates, (C) saliva-coated hydroxyapatite discs, or (D) saliva-coated dentin slices at 37°C for 24 h in the presence or absence of Lp.LTA at 3, 10, or 30 μg/ml. Lp.LTA-treated <i>S</i>. <i>mutans</i> biofilms were visualized by scanning electron microscopy (magnification: × 5,000 and × 30,000).</p

Inhibition of <i>S</i>. <i>mutans</i> biofilm formation by <i>L</i>. <i>plantarum</i> LTA lasts till late stages of biofilm development without affecting the bacterial growth.

<p>(A) <i>S</i>. <i>mutans</i> (1 × 10⁸ CFU/ml) was grown on 96-well polystyrene plates at 37°C for 1, 3, 6, 12, 24, or 48 h in the presence or absence of Lp.LTA at 30 μg/ml. Biofilm formation extent was determined by the crystal violet assay. (B) <i>S</i>. <i>mutans</i> (1 × 10⁸ CFU/ml) was grown at shaking condition for 1, 3, 6, 12, or 24 h in the presence of Lp.LTA at 30 μg/ml. <i>S</i>. <i>mutans</i> growth was determined by the optical density at 540 nm with a spectrophotometer. (C) <i>S</i>. <i>mutans</i> (1 × 10⁸ CFU/ml) was grown in the presence of Lp.LTA at 10 or 30 μg/ml on Lp.LTA-uncoated polystyrene plates (Co-treated) or was grown on the plates pre-coated with Lp.LTA at 10 or 30 μg/ml (Pre-coated) at 37°C for 24 h. (D) <i>S</i>. <i>mutans</i> (1 × 10⁸ CFU/ml) was grown on polystyrene plates at 37°C for 24 h, and then supernatant containing planktonic bacteria was removed. Pre-formed biofilm was treated with Lp.LTA (10 or 30 μg/ml) and further incubated at 37°C for 6 h. Biofilm formation was determined by a crystal violet assay. Data are mean values ± S.D. of triplicate samples. Asterisks, significant induction at <i>P</i> < 0.05 compared with non-treatment control group.</p