Mitis group streptococci are opportunistic pathogens residing in the oral cavity, where they produce hydrogen peroxide (H 2 O 2 ), a key virulence factor contributing to their pathogenesis. We previously demonstrated that these bacteria kill the nematode Caenorhabditis elegans through H 2 O 2 production. Metformin, a widely used biguanide drug for managing blood glucose levels, has shown promising effects on aging by extending...