2019 Volume 57 Issue 1 Pages 1-6
Streptococcus gordonii, an early colonizer of dental plaque biofilm, expresses the surface protein adhesin SspA/B, by which the bacterium binds to salivary agglutinin (gp340). SspA/B has an exten sive homology with PAc, a surface adhesin of Streptococcus mutans, thus S.gordonii competes with S.mutans for the same niche environment in salivary pellicles. The aim of this study was to develop an anti-adherence agent that enables control of cariogenic S. mutans biofilm, for which we used the streptococcal SspA/B peptide analog Ssp(A4K-A11K). Our results showed that Ssp(A4K-A11K) significantly bound to saliva and inhibited adhesion of S.mutans to saliva-coated surfaces. Pretreatment with Ssp(A4K-A11K) significantly attenuated biofilm formation via an antagonistic mechanism, while the analog was less effective on adherence and biofilm formation of commensal streptococci. Notably,Ssp(A4K-A11K) treatment delayed a drop in pH in culture medium to a critical level. These findings will contribute to development of techniques to control cariogenic biofilm.
