The present invention provides compositions, medicaments, and methods for the treatment or prophylaxis of conditions associated with the binding of Streptococcus mutans to teeth. Specifically, the present invention provides a method for preventing dental caries and infective endocarditis in a subject by treating the subject's oral cavity with a composition or medicament comprising the competence stimulating peptide (CSP) of the causative bacterium, which inhibits the ability of the said bacteria to attach to the surface of teeth. Novel anti-caries compositions using the CSP are also disclosed.