Gluconeogenic growth of Vibrio cholerae is important for competing with host gut microbiota.

PURPOSE: The gastrointestinal tract is home to thousands of commensal bacterial species. Therefore, competition for nutrients is paramount for successful bacterial pathogen invasion of intestinal ecosystems. The human pathogen Vibrio cholerae, the causative agent of the severe diarrhoeal disease, cholera, is able to colonize the small intestine, which is protected by mucus. However, it is unclear which metabolic pathways or nutrients V. cholerae utilizes during intestinal colonization and growth. METHODOLOGY: In this study, we investigated the effect of various metabolic key genes, including those involved in the gluconeogenesis pathway, on V. cholerae physiology and in vivo colonization. RESULTS: We found that gluconeogenesis is important for infant mouse colonization. Growth assays showed that mutations in the key components of gluconeogenesis pathway, PpsA and PckA, lead to a growth defect in a minimal medium supplemented with mucin as a carbon source. Furthermore, the ppsA/pckA mutants colonized poorly in the adult mouse intestine, particularly when more gut commensal flora are present. CONCLUSION: Gluconeogenesis biosynthesis is important for the successful colonization of V. cholerae in a niche that is full of competing microbiota.