A Tooth-binding Antimicrobial Peptide Against Streptococcus Mutans

Purpose Research of a kind of dentotropic antimicrobial peptide(AMP)to improve the antibacterial efficacy of PI.Methods Diphosphoserine peptide was selected as the dentotropic micelle to improve the tooth-binding efficacy of Polyphemusin I(PI),Double Phosphorylated Serine-Polyphemusin I(DPS-PI)was conceived and compounded.A test of antibacterial annulus was conducted to determine the minimum inhibitory concentration of the PI against streptococcus mutans(S.mutans).The bovine enamel sheets were made and treated with PI and DPS-PI,then the surface morphology were observed by Electronic Microscope(EM)and elementary composition were detected by Energy Dispersive Spectrometer(EDS).The antibacterial effect of Antimicrobial Peptides(AMPs)-treated enamel sheets were detected by the formation of plaque biofilm of S.mutans,the activity of S.mutans on the AMPs-treated enamel sheets were detected by LIVE-DEAD stain and the growth situation of S.mutans on the AMPs-treated enamel sheets.The antimicrobial effect for plaque biofilm were also detected by incisor surfaces of rabbits.Results The minimum inhibitory concentration of the PI and the DPS-PI were 40?g/ml and 80?g/ml.The difference between the diameters of the PI and the DPS-PI had no statistical significance(P>0.05).The enamel sheets of DPS-PI group have a different surface morphology compared with other groups and contained a higher content of Carbon(C)and nitrogen(N).The Optical Density(OD)of DPS-PI group is Significantly smaller compared with the groups of PI with time going(P<0.05).The incisor surfaces of rabbits treated with DPS-PI developed obviously less dental plaque biofilm than the surfaces treated with PI in vivo.Conclusion The diphosphoserine can improve the affinity of the PI to hydroxyapatite while barely affecting its antibacterial effect.