In Silico Identification of Dual-Action Compounds Targeting TLR2 and Streptococcus mutans Proteins for the Prevention of Early Childhood Caries

Background/Objectives: Early childhood caries (ECC) remains a major public health concern, with Streptococcus mutans as a primary etiological agent. Current treatments rely on broad-spectrum antimicrobials, which can disrupt the oral microbiome and promote resistance. This study applied a structure-based in silico pipeline to identify molecule modulators of Toll-like receptor 2 (TLR2), a key host receptor implicated in ECC, and to explore their binding potential against major S. mutans proteins. Methods: ECC-related genes were collected from public databases and analyzed by functional enrichment and protein–protein interaction (PPI) network analysis. Hub genes were ranked using centrality algorithms. Virtual screening on TLR2 (DrugCLIP) was followed by molecular docking of selected compounds against the TLR1/TLR2 heterodimer and 50 S. mutans proteins, complemented by in silico absorption, distribution, metabolism, excretion, and toxicity (ADMET) profiling. Results: Fifty-four ECC-related genes and nine hub genes were identified, with TLR2 and cathelicidin antimicrobial peptide (CAMP) as central nodes. Virtual screening yielded five lead compounds fulfilling drug-likeness and toxicity criteria. Docking to TLR1/TLR2 showed favorable binding energies, with Z7684613096 showing the most consistent binding. V026-2549 displayed the highest number of strong interactions with S. mutans targets, including dTDP-glucose 4,6-dehydratase (rmlB), NADP-dependent glyceraldehyde-3-phosphate dehydrogenase (gapN), glucosyltransferase C (gtfC), and 5-methyltetrahydropteroyltriglutamate-homocysteine methyltransferase (metE). Conclusions: Five candidate compounds with promising dual activity against TLR1/TLR2 and S. mutans proteins were prioritized for experimental validation, including TLR2 functional assays and in vitro anti-biofilm studies.