The present invention relates to: an antibacterial composition for uracil auxotrophic (URA-) bacteria, containing, as active ingredients, uracil, a uracil precursor, a uracil analog or a non-pathogenic microorganism which produces uracil or a composition for preventing cell damage caused by uracil secretory (URA+) bacteria, containing a reactive oxygen species scavenger (ROS scavenger) as an active ingredient. In addition, the present invention relates to: antibacterial or cell-damage preventing food or feed containing the composition a method for regulating dual oxidase activity, reactive oxygen species generation or the level of the reactive oxygen species with respect to a cell a method for preparing a cell of which the dual oxidase activity, reactive oxygen species generation or the level of the reactive oxygen species are regulated and a method for providing information on whether or not the isolated bacteria has pathogenicity in the intestines. The composition, according to the present invention, has the effect of preventing diseases caused by bacteria according to a mechanism which was not previously known. Further, a treatment strategy can be easily established through classification of bacteria, according to criteria that can be easily identified, and thus the present invention can be useful for preventing diseases caused by bacteria and establishing treatment strategies.La présente invention concerne : une composition antibactérienne servant à lutter contre des bactéries auxotrophes pour luracile (URA), contenant, en tant que principes actifs, de luracile, un précurseur de luracile, un micro-organisme analogue de luracile ou non pathogène qui produit de luracile ou une composition pour prévenir laltération cellulaire provoquée par les bactéries secrétant de luracile (URA+), contenant un piégeur despèces réactives de loxygène (piégeur ROS) en tant quingrédient actif. En outre, la présente invention concerne : des aliments antibactériens ou empêchant un endo
