Pyruvate metabolism is involved in adaptability and cariogenicity of <i>Streptococcus mutans</i>

Dental caries is a biofilm-mediated disease that arises from polymicrobial dysbiosis in dental plaque. Among these microorganisms, Streptococcus mutans plays a prominent role because of its strong capacity to metabolize fermentable carbohydrates into organic acids that drive enamel demineralization. Central to this process is pyruvate, a key metabolic intermediate that connects glycolysis, energy production, biosynthesis, and stress adaptation. Pyruvate metabolism in S. mutans directs carbon flow into various pathways that contribute to its cariogenic potential, including acidogenesis, biofilm formation, and oxidative stress tolerance. This review explores the multifaceted roles of pyruvate in S. mutans, emphasizing its involvement in the production of lactate, acetate, formate, and branched-chain amino acids. We also discuss the regulatory mechanisms that control pyruvate metabolism, such as the Pta-Ack pathway, LrgAB-mediated pyruvate transport, and transcriptional regulation by CcpA/CodY. Furthermore, we highlight promising strategies for caries prevention, including the targeting of pyruvate metabolism using natural compounds and metabolic inhibitors. Future research should focus on elucidating the regulatory networks governing pyruvate metabolism, the metabolic byproducts, and the impact of disrupting pyruvate-based metabolic crosstalk in polymicrobial biofilms. Understanding how pyruvate functions as a carrier or precursor metabolite in central carbon metabolism of S. mutans and its regulation of survival and metabolic processes will have significant implications for caries prevention.