Systematic analysis of the glucose-PTS in <i>Streptococcus sanguinis</i> highlighted its importance in central metabolism and bacterial fitness

Management of carbohydrate metabolism and environmental stress is key to the survival of oral commensal species such as <i>S. sanguinis</i>. Antagonism of oral pathobionts and modulation of the environmental pH and oxidative potential by commensals are crucial to the maintenance of microbial homeostasis and prevention of oral diseases including dental caries. It is therefore vital to understand how these species regulate sugar fermentation, production of acids and ammonia, and stress management in an environment known for a feast-and-famine cycle of carbohydrates and similar fluctuations in pH and oxygen tension. Here, we detail that genetic alterations of the glucose-PTS transporter in <i>S. sanguinis</i> can significantly affect the regulation of factors required for bacterial fitness and homeostatic ability independent of known catabolic regulators. It is then discussed how these changes may impact the survival of streptococcal species and affect caries onset.