The gastrointestinal tract is a reservoir for opportunistic pathogens or pathobionts, which benefit from the disruption of the intestinal microbiota balance or dysbiosis to invade and infect susceptible patients. Vancomycin-resistant enterococci (VRE) originate from the gastrointestinal tract where VRE overgrowth precedes bloodstream infections and transmission. Understanding mechanisms responsible for intestinal colonization resistance to VRE is critical to combat infections and limit spread of antibiotic resistance. Given recent studies that showed the effectiveness of fecal microbiota transplantation, use of commensal bacteria is an attractive strategy to prevent VRE. The project REMOVE aims to identify which commensal bacteria can promote colonization resistance against VRE in a pre-clinical model. To reach this objective we will combine high-throughput sequencing techniques and mathematical modeling of the gut microbiota composition in an antibiotic-treated mouse model of VRE infection. The knowledge gained by REMOVE will provide anti-VRE commensal bacteria as alternatives to antibiotics and as valuable markers of prognostic and diagnostic of antibiotic-induced dysbiosis