Activity of Synthetic Antimicrobial Peptide GH12 against Oral Streptococci
Controlling the growth of cariogenic microorganisms such as oral streptococci is an adjunct therapy for caries-active individuals to prevent and treat caries. Here we investigated the antimicrobial activity of the synthetic amphipathic α- helical antimicrobial peptide GH12 (GLLWHLLHHLLH-NH 2 ) against oral streptococci in vitro. Circular dichroism studies showed that GH12 takes on an α-helical conformation in the presence of membrane-mimicking solvents, and reversedphase high-performance liquid chromatography studies showed that GH12 remains stable in saliva. The peptide showed bactericidal activity against oral streptococci, with minimum inhibitory concentrations ranging from 6.7 to 32.0 μg/ml. GH12 concentrations 4-fold higher than the minimum bactericidal concentration completely killed oral streptococci wit
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