Potential Of A Novel HAp-binding Antimicrobial Peptide For Oral Pathogen Control And Its Property In Human Saliva

Controlling and reducing the formation of pathogenic biofilm on tooth surface is the key to the prevention and treatment of the biofilm-associated oral diseases. Antimicrobial peptides(AMPs), considered to be a suitable substitute for conventional antibiotics, have been extensively studied for the control of bacterial infection. But their application in the oral cavity was limited due to the rapid dilution and degradation effect of human saliva. To solve this problem, a novel HAp-binding antimicrobial peptide(HBAMP), which is based on the fusion of a specific HAp-binding heptapeptide(HBP7) domain and a broad-spectrum antimicrobial peptide domain with GGG as a linker, have been developed in our laboratory. HBAMP was supposed to form an antimicrobial bioactive coating on tooth surface to inhibit the formation of biofilms. In this study, we investigated its binding behavior, antibacterial activity and physical property in human saliva. Fluorescence images showed that HBAMP could adhere to the surface of hydroxyapatite discs quickly and stably. The results of bacterial susceptibility assay indicated that HBAMP had good antibacterial activity against the bacteria tested. Confocal Laser Scanning Microscope(CLSM) images showed that HBAMP had significant inhibition effect on S. mutans biofilms. High Performance Liquid Chromatography(HPLC) chromatograms showed that HBAMP had satisfactory stability in human saliva. Cytocompatibility studies demonstrated that HBAMP had little effect on the proliferation of human gingival fibroblasts. Our findings suggest that HBAMP could adsorb on tooth surface to provide long-term antimicrobial efficacy and have great potential clinical applications in oral cavity.