The Kreth lab investigates fundamental processes of commensal bacterial interactions in the oral biofilm. Under healthy conditions, the commensal oral microbes maintain a beneficial homeostatic state protecting the host from diseases. Host behavior and environmental changes can promote a shift in the microbial composition of the oral biofilm. Pathobionts are able to increase in numbers and an overall decline in commensal species can be observed. On the molecular level, bacteria maintain the ecological balance by diverse interactions, both antagonistic and synergistic. We aim to identify and characterize the molecular mechanisms that promote commensal species to better understand the healthy oral microbiome.