Dental caries, a widespread chronic disease, is primarily driven by the biofilm-forming bacterium Streptococcus mutans, which adheres to tooth surfaces via the surface protein antigen I/II (Ag I/II, PDB: 3IPK). Overuse of traditional antimicrobial agents in oral care contributes to antimicrobial resistance (AMR), highlighting the need for natural, sustainable alternatives. This study investigates cranberry-derived procyanidin A2 as a potential in- hibitor of bacterial adhesion. Using UCSF Chimera and AutoDock Vina, we conducted molecular docking simulations to evaluate the binding affinity of six compounds—including procyanidin A2, quercetin, procyanidin B1, cyanidin- 3-galactoside, glucose and sucrose—against the 3IPK protein. To assess solution-phase behavior, we also performed molecular dynamics (MD) simula- tions in OpenMM. Procyanidin A2 exhibited the strongest binding affinity (-10.2 kcal/mol) and maintained conformational stability in aqueous environments, supporting its potential as a reliable inhibitor. Control compounds such as glucose and sucrose showed weak binding, reinforcing the specificity of PACs. These findings provide a promising computational foundation for future in vitro experiments and contribute to the development of AMR-conscious strategies for caries prevention.
Y. B. Wang (Sat,) studied this question.