Effects of Lactobacillus reuteri-derived biosurfactant on the gene expression profi le of essential adhesion genes (gtfB, gtfC and ftf) of Streptococcus mutans

Streptococci are the main causative agents in plaque formation and mutans streptococci are the principle etiological agent of dental plaque and caries. The process of biofilm formation is a step-wise process, starting with adhesion of planktonic cells to the surfaces. It is now a well known fact that expression of glucosyltransferases (gtfs) and fructosyltransferase (ftf) genes play a critical role in the initial adhesion of Streptococcus mutans to the tooth surface, which results in the formation of dental plaques and consequently caries and other periodontal diseases.

In the present study, we have determined the effect of biosurfactants purified from Lactobacillus reuteri (DSM20016) culture on gene expression profile of gftB/C and fft of S. mutans (ATCC35668) using quantitative real-time polymerase chain reaction.

The application of biosurfactant caused considerable down-regulation of the expression of all three genes under study. The reduction in gene expression was statistically very significant (P > 0.0001 for all three genes).

Inhibition of these genes by the extracted L. reuteri biosurfactant shows the emergence of a powerful alternative to the presently practicing alternatives. In view of the importance of these gene products for S. mutans attachment to the tooth surface, which is the initial important step in biofilm production and dental caries, we believe that the biosurfactant prepared in this study could be considered as a step ahead in dental caries prevention.