Methionine biosynthesis as a key metabolic pathway for antimicrobial drug discovery in Streptococcus mutans.

Streptococcus mutans, a Gram-positive, facultative anaerobic bacterium, is a key contributor to dental caries. It forms biofilms to colonize the tooth surface, has stress resistance mechanisms to survive the fluctuating oral environment, and produces virulence factors, all of which cause enamel demineralization, acid production, and caries development. Traditional antimicrobial strategies target central metabolic pathways in S. mutans, but most enzymes are conserved between humans and bacteria. However, one prospective approach is to target methionine biosynthesis. This pathway is essential for protein synthesis, methylation reactions, and oxidative stress resistance, supporting bacterial growth, biofilm formation, and cariogenic potential. Notably, its selective inhibition can be achieved because this pathway is absent in humans. Therefore, targeting enzymes of this pathway could halt bacterial growth and virulence, offering a novel antimicrobial strategy to treat S. mutans infections.