Use of mutants in the elucidation of virulence of Streptococcus mutans.

Abstract

In the presence of sucrose, Streptococcus mutans displays certain unique metabolic activities which are believed to be important factors in determining its virulence. Of the various carbohydrates metabolized by S. mutans, only sucrose is utilized for the production of acid, fructans and glucans (1,2). The adhesive water-insoluble glucans have been shown to be most important for the attachment of cells of S. mutans to smooth surfaces (1,3,5); probably both the water-insoluble and water-soluble glucans are required for the cell to cell aggregation which results in plaque production (6,7). Several laboratories have employed bacterial mutants and model systems of cell adherence and aggregation to study the cariogenic nature of S. mutans (5,8–13). We present results of certain biochemical activities of mutants of S. mutans strain 6715 and attempt to relate these findings to the cariogenic and immunogenic nature of these organisms.