Multi-Pronged Approach for Targeting Oral Biofilms

The oral microbiome is a complex system consisting of numerous bacterial species that plays host to both beneficial and harmful organisms. Among the pathogenic species in the oral cavity is <i>Streptococcus mutans </i>(<i>S. mutans</i>), the primary agent responsible for dental caries. Different antimicrobial-based strategies have been developed to tackle this problem, but the rise of antibiotic resistance among microorganisms necessitated the development of new and effective therapeutics. One such solution is the <i>de novo</i> antimicrobial peptide (AMP), GH12, which has showed potency against cariogenic bacteria. GH12 has a high content of α-helical structures that facilitate pore formation on bacterial membranes. Quorum sensing molecules such as competence stimulating peptides (CSP) have been identified as communicator molecules in bacterial species that are used to monitor not only their own but other species in their surroundings. Recently, polyserotonin (PSe) has emerged as a photothermally active nanomaterial that shows promise towards biomedical applications. In this work, I made a cocktail combining all three of the aforementioned components—AMP for bacterial killing, CSP for targeting, and PSe for localized heating—to develop a multi-pronged approach aimed to increase antibiofilm efficacy. My findings indicate that the presence of both peptides, membrane damaging and competence stimulating, in conjunction with the photothermally active PSe, effectively inhibited the growth of <i>S. mutans</i> in both planktonic and biofilm states. Overall, these results reinforced that the strategic use of multi-pronged therapeutic approaches could reduce cariogenic bacteria within the oral microbiome.