PhageOS - Prophage-Encoded Functional Reprogramming of Veillonella atypica’s Commensal-to-Accessory Pathogen Transition in the Oral Microbiome in Relation to Periodontitis

Periodontitis is a chronic inflammatory disease linked to systemic health problems, arising from microbial dysbiosis and imbalanced immune response in the oral cavity. The oral microbiome continually adapts to internal and external changes through horizontal gene transfer, with phage-mediated transduction being one of major mechanisms that can supply bacteria with new genes, altering their functional roles. Notably, Veillonella atypica, generally beneficial oral bacteria, may adapt an accessory pathogen role during periodontitis, though the drivers of its functional shift remain unclear. The goal of this project is to determine how prophage-encoded genes influence V. atypica’s transformation from a commensal to a dysbiotic biofilm-supporting accessory periopathogen. To address this, we will perform comparative genomics analysis across V. atypica strains from plaque and saliva samples from periodontitis patients and healthy controls. We will further examine prophage gene activation under oxidative stress using bulk and single-cell SLAM-seq. Finally, we will test biofilm behavior of selected V. atypica strains under oxidative stress and baseline conditions. Findings of this project will be disseminated through two open-access scientific manuscripts, two presentations at leading international conferences, multiple dataset deposition into public repositories, as well as through activities, aimed at the broader public.