Streptococcus mutans (S. mutans) has important virulence factors related to the etiology and pathogenesis of dental caries. Through mechanism of adhesion to a solid surface, S. mutans is able to colonize the oral cavity and form dental biofilm, which is composed of a matrix of exopolysaccharides that affect the physical and biochemical structure of the biofilm. The additional properties that allow S. mutans to colonize the oral cavity include the generation of acid (acidogenicity), the interaction with other bacterial species colonizing this ecosystem and the ability to survive in an acidic environment. In addition, these microorganisms can tolerate the acidic environment (aciduricity) due, at least in part, to the ATPases located in the plasma membrane responsible for the extrusion of the cytoplasmic proton. Changes in environmental pH can modify the fatty acid and proteins composition of the plasma membrane of S. mutans, inducing the alteration of its permeability. The different dental surfaces or biofilms can affect the lipid composition of the bacterial membrane by altering the virulence factors of S. mutans, such as acid survival and ATPase activity.
Part of the book: Staphylococcus and Streptococcus